Tibial Plateau Levelling Osteotomy in Cats: A Retrospective Study of 23 Cases

Abstract

This study aimed to describe tibial plateau levelling osteotomy procedures in cats with cranial cruciate ligament ruptures, assessing related complications (intra- and postoperative) and long-term outcomes after mini/micro-FIXIN T/L plate stabilizations.

The study design was retrospective.

A total of 23 cats with cranial cruciate ligament ruptures were selected, each undergoing general and orthopaedic clinical assessments and subjected to tibial plateau levelling osteotomy procedures, with simultaneous exploratory mini-arthrotomies. We collected medical histories and reporting data, complete blood and urine test results and imaging diagnostics (echocardiography, radiography under sedation). Remnant cranial cruciate ligament histology was available on seven occasions. Follow-up orthopaedic examinations and radiographs were done at postoperative months 1, 2, 4, 6, 12, and 24.

The overall complication rate was 24% (inadequate compression of osteotomy surfaces, 2; fibula fracture, 3; breakage of screws and tibial crest, 1), only one event (4%) being major. Concomitant medial meniscal injury was evident in 76% of joints. During 24 months of follow-up, all patients fully recovered, without recurrences or significant osteoarthritic deterioration.

Preliminary study results indicate that tibial plateau levelling osteotomy procedures in feline species confer good long-term limb function, with minimal progression of osteoarthritis.

Keywords

TPLO - cranial cruciate ligament rupture - meniscal lesion - 24-month follow-up - cat

Introduction

Cruciate ligament rupture in dogs is the most commonly seen and frequently analysed disorder in veterinary orthopaedics.[1] [2] [3] [4] [5] [6] [7] [8] The many etiopathogenetic factors cited include breed, weight, age, physical activity, skeletal considerations (axial deviations, patellar luxation, tibial plateau angle [TPA], distal-to-proximal tibial angle ratio, intercondylar notch conformation), and other influences (chronic inflammation, pharmacologic therapies, hereditary components).[1] [2] [3] [4] [5] [6] [7] [8] Rupture is typically a chronic, degenerative process, in which partial lesions often occur, although the percentage of bilateral tears seems to vary (40–60%).[2] [3] [4] [5] [6] [7] [8] For the most part, tibial plateau levelling osteotomy (TPLO), tibial tuberosity (TT) advancement, and extracapsular technique are the treatments of choice.[1] Tibial plateau levelling osteotomy is perhaps the most often performed and widely studied orthopaedic surgical procedure in dogs, generating an abundance of scientific data.[1] [2] [3] [4] [5] [6] [7] [8]

In the feline species, data on cranial cruciate ligament (CrCL) rupture as an isolated finding are limited and fragmentary. Breed and sex are not relevant, average age is >8 years, and average weight is >5 kg.[9] [10] [11] [12] [13] There is a high incidence (67%) of associated meniscal lesions, and complete tears (rarely bilateral) are the rule.[9] [11] [12] [13] [14] [15] No history of trauma or axial deviations is evident, and on average, the TPA tends to exceed that of healthy subjects (25 vs. 21 degrees).[16] [17] Dystrophic mineralization is visible radiographically within the cranial compartment, along with distal dislocation of the sesamoid popliteal bone.[11] The ligament is affected by metaplastic changes rather than by a true degeneration, as in dogs.[14] Many surgical techniques have been applied with variable results.[10] [11] [12] [13] [18] [19] [20] [21] [22] There is simply no agreement in the literature on procedural efficacies, with various sources reaching conflicting conclusions.[9] [10] [11] [12] [13] [18] [19] [23] [24] [25]

The aim of this investigation was to describe the TPLO technique in cats, evaluating the long-term efficacy of this approach in preventing progression of osteoarthritis (OA).

Materials and Methods

Study Population

A series of 23 cats (differing breeds and sexes) presented to our clinic for acute hindlimb lameness. All had previously received non-steroidal analgesics (non-steroidal anti-inflammatory drugs), without meaningful clinical improvement. Each underwent general and orthopaedic clinical examinations, complete blood and urine testing, echocardiography and radiographic studies under sedation. Haematologic or echocardiography changes prohibiting anaesthesia were grounds for exclusion, as were other orthopaedic disorders or multiligament stifle joint injuries. Lameness was graded subjectively as follows: 0, none; 1, mild (slow-motion video finding); 2, moderate (weight-bearing, every step); 3, severe (non-weight-bearing at times); 4, constant (non-weight-bearing). Radiographic studies included lateral and standard ventrodorsal projection of pelvis, mediolateral projections of both stifle joints and tarsi at 90 degrees, mediolateral projection of knee, with cranial tibial thrust (CTT), caudocranial sagittal projection of stifle joint and tibia (bilateral), axial projection of femur, assessing femoral neck anteversion angle, stressed projections to evaluate collateral and caudal cruciate ligament integrity.[26] We measured TPA, femoral neck anteversion angle and anatomical lateral distal femoral angle in all subjects.

Osteoarthritis was gauged on radiographs using an existing scale for cats, designating soft tissue swelling and increasing subchondral radiopacity as 0 (not visible) or 1 (visible).[27] [28] Osteophytes, enthesophytes and soft tissue mineralization were graded from 0 to 3 (0, normal; 1, ≤1 mm; 2, >1 but ≤3 mm; 3, >3 mm). In accordance with Freire and colleagues, we subjectively graded radiographic changes (0–4) as follows: 0, normal; 1, minimal; 2, mild; 3, moderate; 4, severe.[12] [13] [29] Given all above ratings, radiographic scores (0–10) of OA (0, none identifiable; 1–3, mild; 4–6, moderate; 7–9, severe; 10, extreme OA/ankylosis) were then assigned over time. All preoperative radiographic metrics were obtained under the same deep sedation protocol: methadone (Semfortan; Dechra, Northwich, England, United Kingdom), 0.2 mg/kg intramuscularly; dexmedetomidine (Dexdomitor; Zoetis, Parsippany, NJ), 5 μg/kg intramuscularly.

To ensure correct osteotomy positioning, three values were obtained from mediolateral radiographs of stifle joints, including D1 (linear distance perpendicular to mechanical axis of tibia [as in TPA measurement], from TT to intended osteotomy line), D2 (distance bordering tibia cranioproximally, from TT to tibial exit of intended osteotomy), D3 (distance from most caudal tibial plateau point to exit of intended osteotomy line, along caudal border of tibia). Our goal was at least 7 to 8 mm for D1, to avoid tibial crest fractures.

Surgical Procedures

All TPLO and simultaneous exploratory mini-arthrotomy procedures entailed the following anaesthetic protocol: premedication (methadone, 0.2 mg/kg intramuscularly; dexmedetomidine, 4 μg/kg intramuscularly), induction (propofol, 3–4 mg/kg intravenously) and maintenance (isoflurane, end-tidal value of 1.1–1.3 on 45% oxygen). Peripheral nerve blocks were done regularly, using 0.5% bupivacaine for lumbar plexus (0.1 mL/kg; lateral pre-iliac technique) and sciatic nerve (0.05 mL/kg; lateral approach) blockade, assisted by nerve stimulator (Stimuplex HNS 12 Nerve Stimulator; B. Braun Medical Inc., Melsungen, Germany). Cefazolin (20 mg/kg intravenously) was given 20 minutes prior to surgery and again at 90-minute intervals until the end of surgery.

In each case, we adopted a standard medial approach to proximal tibia. Using a 12-mm saw blade (Synthes, Solothurn, Switzerland), all osteotomy lines created were based on preoperative measurements. Tibial plateau rotational magnitudes were derived from a TPLO chart to achieve a 5-degree postoperative TPA. Given the surgical field limitations, TPLO jig use was untenable. We placed a Kirschner wire (1.2-mm diameter) in the tibial plateau segment for rotation, introducing another (0.8-mm diameter) through the proximal aspect of TT into tibial plateau segment for temporary fixation. Before affixing plates, there was CTT testing. Overall, we installed pre-contoured, titanium locking plates held by four screws (conically coupled; FIXIN; Intrauma, Rivoli, Italy) in 25 stifle joints (two bilateral), for a total of 19 mini-series plates (2.5-mm screws, except case 13 [1.9-mm screws]), 17 T-shaped (25-mm long, 1.2-mm thick) and 2 L-shaped (26 mm long, 1.2 mm thick) designs plus 6 T-shaped micro-series plates (23-mm long, 1.2-mm thick), with 1.7-mm screws. Compression of osteotomy surfaces was achieved through tipped self-locking reduction forceps (Synthes), securing screws alternately to proximal and distal segments of tibia. These pre-contoured plates did not require force to interface with bone. In case any proximal screw interfered with a temporary fixation wire, the latter was removed maintaining reduction via forceps.

Medial mini-arthrotomy followed, avoiding the medial patellofemoral ligament incision and its alar cartilage. This allowed meticulous exploration of entire joints, with meniscectomy or meniscal suturing (if needed), positioning two Gelpi retractors at 90 degrees to maximize visible joint space. To suture medial meniscal cranial horn, we used a single, horizontal, U-shaped stitch (2/0 polydioxanone). Joint capsule and fascia were sutured (2/0 polydioxanone) through separate and continuous stitches, respectively, closing remaining layers in a routine manner (subcutis, 3/0 poliglecaprone; skin, 3/0 polyamide). On seven occasions, CrCL material was sufficient for postoperative histology.

Postoperative Care

Soft bandages were routinely applied for 5 days postoperatively, even after next-day discharge. Postoperative therapy was the same for all patients, consisting of methadone (Semfortan; Dechra), 0.1 mg/kg intramuscularly, every 6 hours for 24 hours; amoxicillin–clavulanic acid (Synulox; Zoetis), 20 mg/kg, every 12 hours for 7 days; meloxicam (Metacam; Boehringer Ingelheim, Ingelheim, Germany), 0.1 mg/kg, every 24 hours for 5 days and gabapentin, 6 mg/kg, every 24 hours for 30 days. Skin stitches were removed 15 days after surgery. Restraint was essential, calling for a room to walk freely but devoid of fixtures that promote jumping for 2 months postoperatively.

Clinical and Radiographic Outcomes

We evaluated surgical sites, limb function and lameness on postoperative day 1, upon suture removal and at each radiographic follow-up (i.e., immediately after surgery and at months 1, 2, 4, 6, 12, and 24). Each radiographic checkpoint included 90 degrees mediolateral and caudocranial sagittal projections of treated joints, without sedation. Immediately, after surgery, we examined osteotomy and implant positioning, limb alignment and TPA achieved, while in the subsequent checks we assessed bone union (defined as complete bone healing, presence of bridging callus or osteotomy line disappearance). As in earlier studies, bone union scores reflected levels of healing (1, poor [<25%]; 2, fair [25–50%]; 3, good [>50% but <75%]; 4, excellent [>75%]).[12] [30] Lameness classification relied on a scale applied preoperatively. Finally, our previously described scoring system served to grade OA at time points 0 (T0, postoperative), 1 (T1, 12 months) and 2 (T2, 24 months), comparing T0 and T2 levels to ascertain OA progression.

Complications

Intraoperative complications were defined as those occurring during or immediately after surgery, upon radiographic examination. Postoperative complications were those developing >24 hours postoperatively. Complications associated with surgical procedures were deemed major if revision surgery was necessary, and any events managed without further surgery qualified as minor.

Results

All 23 subjects lived indoors; average weight was 6.8 kg (range, 5.5–9 kg); average age was 8.7 years (range, 4–12 years). Recorded breeds were as follows: European, 13; Maine Coon, 5; British Shorthair, 3; and Norwegian, 2. There were 14 males (all neutered) and 9 females (spayed, 8; intact, 1). Only one cat was <7 years old. Two bilateral tears occurred (>1 year apart), the remaining 21 being unilateral (right, 15; left, 10). Although many owners could not attest to any trauma, jumps leading to lameness were directly witnessed in 11 cases. At presentation, lameness was grade 2 (10/25) or 3 (15/25), with pain on stifle extension, positive drawer testing (subjects awake) and non-appreciable joint swelling. All worsened to grade 4 after forced stifle extension (positive stress test).

On X-rays, cranial displacements of tibia were apparent in mediolateral projections with CTT test. In all cases, soft tissue swelling and increasing subchondral radiopacity were absent at diagnosis. Osteophytes and enthesophytes (graded 0–3) were largely low grade (grade 0, 7 joints; grade 1, 17 joints; grade 2, 1 joint), whereas soft tissue mineralization proved more extensive (grade 0, 8 joints; grade 1, 7 joints; grade 2, 8 joints; grade 3, 2 joints), with approximately 68% (17/25) of joints examined showing dystrophic cranial compartment mineralization. The average Freire-scale grade was 1.44 (grade 0, 1 joint; grade 1, 14 joints; grade 2, 8 joints; grade 3, 2 joints) and average OA score was 1.6 (0, 1 joint; 1, 16 joints; 2, 3 joints; 3, 2 joints; 4, 3 joints). No subject presented with patellar luxation or axial deviation of femur or tibia. Average TPA was 24.8 degrees (range, 21–28 degrees), with anatomical lateral distal femoral angle and femoral neck anteversion angle averaging 90 ± 2.5 degrees and 20 ± 5 degrees, respectively.

At the time of surgery, all subjects demonstrated complete CrCL tears, often with tears of medial meniscus (19/25). There were 16 longitudinal ‘bucket handle’ lesions and 3 avulsions of cranial horn (all three Maine Coon breed). In one instance (case 12), it was possible to suture the cranial horn using a single, horizontal, U-shaped stitch (2/0 polydioxanone). In terms of clinical and radiographic postoperative outcomes, five minor intraoperative complications emerged, including inadequate compression of osteotomy surfaces (two cases) and fibula fracture (three cases) – all resolved without further surgery. The average postoperative TPA was 5.4 degrees (range, 2–7 degrees), incurring just two marked overcorrections (cases 7 and 14) and average postoperative D1 was 6.6 (range, 5–8). No suture dehiscence or infection developed.

Lameness was regularly resolved within 1 month after surgery, with complete (level 4) short-term healing of all osteotomy lines (1 month, 15/25; 2 months, 10/25). No subject showed positive postoperative CTT test, while all still had a positive drawer sign. Only one major postoperative complication arose 1 month after surgery (case 13), marked by breakage of screws and tibial crest after left-sided surgery, due to a leap from a table ([Fig. 1]). Revision surgery was necessary, replacing the screws and tibial crest fixation with Kirschner wire (1.2-mm diameter) and figure-eight tension band cerclage (0.8-mm diameter). This was also the sole instance of postoperative D1 at 5 mm. Apart from case 13, OA did not substantially progress during the 2-year follow-up. ([Fig. 2]). Average OA score at 24 months was 2.28 (0, 1 joint; 1, 13 joints; 2, 2 joints; 3, 3 joints; 4, 2 joints; 5, 2 joints; 6, 1 joint; 7, 1 joint). The average T0–T2 score differential was 0.68, with 10 joints worsening but only 3 progressed from mild to moderate and only 1 evolved from moderate to severe (case 13; [Table 1]). There were no recurrences of lameness and no implants were removed. In histological preparations of seven available CrCL specimens, original collagen fibres were readily identified. Chondroid-like cells were also present, arranged in small groups (vs. rows or columns). Degenerative changes were otherwise lacking.

Fig. 1 Case 13: 1.9 screws and the tibial crest breakage, due to cranial osteotomy with small tuberosity and thin screws (A, B). Revision surgery with 2.5 screws, Kirschner wires and tension band cerclage (C).

Fig. 2 Case 9: minimal progression of arthrosis: postoperatively (A), 1 month (B), 12 months (C), 24 months (D).

Table 1 Medical records

Case number	Breed	Age (years)	Sex	Weight (kg)	Lifestyle	Tibial plateau angle	Meniscal injuries	Surgery and plate	Tibial plateau angle postoperatively	D1	Osteoarthritis T0	Osteoarthritis T2
1	Maine Coon	8	Male neutered	8	Indoor	26 R + 24 L	Longitudinal ‘bucket handle’	Bilateral meniscetomy, T-shaped mini	5 R + 6 L	8 R + 7 L	1	1
2	British Shorthair	9	Female spayed	5.5	Indoor	23	None	R, T-shaped micro	5.5	6	1	1
3	British Shorthair	11	Male neutered	6	Indoor	23	Longitudinal ‘bucket handle’	L, meniscetomy,T-shaped mini	6	7	3	5
4	European	10	Female spayed	5.5	Indoor	24	Longitudinal ‘bucket handle’	R, meniscetomy, T-shaped micro	6	8	4	6
5	European	9	Male neutered	6	Indoor	22	None	Right, T-shaped mini	5	6	1	1
6	European	9	Female spayed	5.5	Indoor	26	Longitudinal ‘bucket handle’	L, meniscetomy, T-shaped micro	7	6	1	1
7	Maine Coon	7	Male neutered	8.5	Indoor	26	Avulsions of the cranial horn	Right, meniscetomy, T-shaped mini	2	7	1	1
8	European	10	Male neutered	7	Indoor	27	Longitudinal ‘bucket handle’	Right, meniscetomy, T-shaped mini	6	6	2	3
9	European	7	Female spayed	6	Indoor	21	None	Right, L-shaped mini	5	8	1	1
10	European	9	Male neutered	6.5	Indoor	22	Longitudinal ‘bucket handle’	Left, meniscetomy, T-shaped mini	6	6	1	2
11	Norwegian	8	Male neutered	8	Indoor	23	Longitudinal ‘bucket handle’	Right, meniscetomy, T-shaped mini	5.5	7	1	1
12	Maine Coon	4	Male neutered	9	Indoor	28	Avulsions of the cranial horn	Right, meniscal suture, T-shaped mini	4.5	8	0	0
13	European	12	Female spayed	6	Indoor	26 R +  26 L	Longitudinal ‘bucket handle’	Bilateral, meniscetomy, T shaped mini with 1.9 screws + revision on the left side with 2.5 screws	6.5 R + 5.5 L	6 R + 5 L	4	4–7 (left side only)
14	European	9	Male neutered	7	Indoor	23	None	Left, L-shaped mini	3	6	1	1
15	European	8	Female intact	5.5	Indoor	26	Longitudinal ‘bucket handle’	R, meniscetomy, T-shaped micro	6.5	6	1	1
16	Norwegian	9	Male neutered	8,5	Indoor	27	Longitudinal ‘bucket handle’	Right, meniscetomy, T-shaped mini	5.5	6	1	2
17	Maine Coon	7	Male neutered	8,5	Indoor	25	Avulsions of the cranial horn	Left, meniscetomy T-shaped mini	5	8	1	1
18	European	10	Female spayed	6	Indoor	26	Longitudinal ‘bucket handle’	L, meniscetomy, T-shaped micro	5.5	6	2	5
19	European	10	Female spayed	6	Indoor	25	None	Left, T-shaped micro	7	6	3	4
20	European	9	Male neutered	6.5	Indoor	23	Longitudinal ‘bucket handle’	Right, meniscetomy, T-shaped mini	5.5	7	2	3
21	Maine Coon	9	Male neutered	8	Indoor	26	None	Right, T-shaped mini	5.5	6	1	3
22	British Shorthair	8	Female spayed	6.5	Indoor	27	Longitudinal ‘bucket handle’	Left, meniscetomy, T-shaped mini	5	6	1	1
23	European	8	Male neutered	7.5	Indoor	25	Longitudinal ‘bucket handle’	Right, meniscetomy, T-shaped mini	5.5	7	1	1
	Summary	Average: 8.7		Average 6.8		Average 24.8	76%		Average 5.4	Average 6.6	Average 1.6	Average 2.28 Average score differential 0.68

Discussion

In our case series, the CrCL rupture does not seem to be breed-related. Neutered (vs. intact) predominance is possibly skewed by greater urban-area neutering inclinations. The average weight (6.8 kg) was also somewhat excessive, compared with 100 healthy cats (8–12 years old) routinely seen at our facility (average weight, 5.2 kg). All patients were aged, healthy, very active indoor cats and enjoyed jumping. This situation may suggest a traumatic etiopathogenesis, although few cases do not allow definitive conclusions. There were various degrees of acute lameness shown by all subjects, with no real signs of chronicity (based on radiographic OA scores) and no swelling or joint effusion. Furthermore, only two instances of bilateral pathology were encountered, each >12 months apart. However, the presence of joint calcifications in a majority of these may be an important consideration, having been documented in healthy aged subjects in our cases and the literature.[28] [29] [31] None of the subjects presented significant axial deviations or patellar dislocation. On the other hand, TPA was slightly higher than reported norms in the literature.[17] Also, 76% of patients displayed concomitant injury of the medial meniscus, indicating high-energy trauma and underscoring the need for surgical therapy in cats. The finding of three avulsions of the cranial horn of medial meniscus, all in Maine Coon, requires future investigations, to understand etiopathogenesis

The exclusive use of FIXIN stabilization materials represents a personal conviction that the size and thickness of such plates are more suitable for feline species. Only four screws are allowed, but their diameters (mini-series, 2.5 mm; micro-series, 1.7 mm) are larger than those permitted by others, imparting greater resistance to weight-loading. This proves advantageous, especially in smaller subjects, where 1.5-mm diameter screws should rightly be used for traditional implants.

In M.F.'s experience with dogs, performing a mini-arthrotomy after TPLO helps improve visualization of the caudal joint compartment, given the levelling of the tibial plateau. In this case series, it was always possible due to a clear clinical diagnosis. Postoperative TPA value was assumed from M.F.'s experience with dogs and the literature.[12] [13] [32] Although all subjects showed positive drawer sign and internal rotational instability, in all cases a negative CTT was achieved. While some cadaveric studies conclude that a postoperative TPA of 5 degrees is inadequate to stabilize stifles in cats with CrCL rupture, all subjects in our series showed excellent clinical outcomes, as previously reported using this technique.[12] [13] [33]

During follow-up, bone healing and clinical resolution proceeded rapidly in all subjects, as congruent with previous reports on TPLO in cats.[12] [13] Even the two cases of overcorrection were free of postoperative complications. The high osteotomy did not affect bone healing or clinical outcome. Progression of OA was also minimal during the 2-year follow-up. The various scoring methods have not contributed to clarity, but it was preferable to adopt existing scales for better outcome comparisons. The use of categories with reference intervals led to our conclusions, with some subjects deteriorating but not straying beyond their reference range. On the other hand, our 24-month follow-up is the longest reported for cats after TPLO. The postoperative radiographic checks for OA were not infrequent, due to the purpose of monitoring the progression of OA but did not involve sedation; the single major complication that occurred indicates the relative procedural safety. It stands as the only instance of tibial crest thickness <6 mm, suggesting that 6 mm may constitute a valid cutpoint for D1 in cats. Finally, the histologic findings afforded by seven cases of CrCL rupture offer support for an injury or overuse etiopathogenesis.[14] [34] [35]

In summary, anamnestic and clinical data, as well as postoperative histologic features in our case series, indicate the possible acute traumatic underpinnings of cruciate ligament rupture in cats, not clearly related to degenerative change. This is different from the condition in dogs and is akin to an overall traumatic cause of CCL rupture. In our cats, the most relevant contributors appear to have been advanced age and highly active indoor-life behaviour, coupled with slightly above-normal weight. The high incidence of concomitant meniscal lesions observed argues in favour of surgery, leaving less justification for conservative therapeutic options, despite some reports suggesting that a conservative approach has better outcomes.[9] [36] Although biomechanical studies have shown failure of TPLO to stabilize the feline stifle, we found that TPLO seems to be safe and effective in the long term and helps to avoid OA progression. There are some limitations in this study, such as a lack of objective gait analysis, a small number of cases and a retrospective nature. The exact etiopathogenesis remains unknown, despite in the majority of our cases, a traumatic origin seemed more likely; comparison with other surgical techniques or conservative therapy is advisable.

Conflict of Interest

None declared.

Acknowledgements

We wish to thank all Anaesthesia and Postoperative Care Unit staff members at the Veterinary Clinic Strada Ovest for their support and professionally rendered patient care.

Ethical Approval

The work detailed herein involved non-experimental, privately owned animals. We routinely followed established and internationally recognized standards for ‘best practice’ of veterinary clinical care, making ethics committee approval an unnecessary publication requirement.

Informed Consent

Written informed consent was granted by all animal subject owners for procedures as specified. No identities (animal or human) are disclosed to warrant further publication consent.

• References

• 1 Bergh MS, Sullivan C, Ferrell CL, Troy J, Budsberg SC. Systematic review of surgical treatments for cranial cruciate ligament disease in dogs. J Am Anim Hosp Assoc 2014; 50 (05) 315-321
• 2 Griffon DJA. A review of the pathogenesis of canine cranial cruciate ligament disease as a basis for future preventive strategies. Vet Surg 2010; 39 (04) 399-409
• 3 Comerford EJ, Smith K, Hayashi K. Update on the aetiopathogenesis of canine cranial cruciate ligament disease. Vet Comp Orthop Traumatol 2011; 24 (02) 91-98
• 4 Spinella G, Arcamone G, Valentini S. Cranial cruciate ligament rupture in dogs: Review on biomechanics, etiopathogenetic factors and rehabilitation. Vet Sci 2021; 8 (09) 186
• 5 Roush JK. Canine cranial cruciate disease: Updating our knowledge about pathogenesis & diagnosis. Tod ays Vet Pract 2013; ; July/August (4): 16-20
• 6 Hynes J, Manfredi JM, Shull SA. Cranial cruciate ligament disease is perceived to be prevalent and is misunderstood in field trial sport. J Am Vet Med Assoc 2023; 261 (11) 1-6
• 7 Boge GS, Engdahl K, Bergström A. et al. Disease-related and overall survival in dogs with cranial cruciate ligament disease, a historical cohort study. Prev Vet Med 2020; 181: 105057
• 8 Cook JL. Cranial cruciate ligament disease in dogs: biology versus biomechanics. Vet Surg 2010; 39 (03) 270-277
• 9 Boge GS, Engdahl K, Moldal ER, Bergström A. Cranial cruciate ligament disease in cats: an epidemiological retrospective study of 50 cats (2011-2016). J Feline Med Surg 2020; 22 (04) 277-284
• 10 Umphlet RC. Feline stifle disease Vet Clinics North America. Small Animal Practice 1993; 23: 897-913
• 11 Harasen GL. Feline cranial cruciate rupture: 17 cases and a review of the literature. Vet Comp Orthop Traumatol 2005; 18 (04) 254-257
• 12 Mindner JK, Bielecki MJ, Scharvogel S, Meiler D. Tibial plateau levelling osteotomy in eleven cats with cranial cruciate ligament rupture. Vet Comp Orthop Traumatol 2016; 29 (06) 528-535
• 13 Tamburro R, Collivignarelli F, Falerno I. et al. Clinical outcomes and stifle osteoarthritis assessment of nine cats before and after tibial plateau levelling osteotomy. Acta Vet (Beogr) 2020; 70 (03) 346-354
• 14 Wessely M, Reese S, Schnabl-Feichter E. Aetiology and pathogenesis of cranial cruciate ligament rupture in cats by histological examination. J Feline Med Surg 2017; 19 (06) 631-637
• 15 Ruthrauff CM, Glerum LE, Gottfried SD. Incidence of meniscal injury in cats with cranial cruciate ligament ruptures. Can Vet J 2011; 52 (10) 1106-1110
• 16 Swanson EA, Tomlinson JL, Dismukes DI, Fox DB. Measurement of femoral and tibial joint reference angles and pelvic limb alignment in cats. Vet Surg 2012; 41 (06) 696-704
• 17 Schnabl E, Reese S, Lorinson K, Lorinson D. Measurement of the tibial plateau angle in cats with and without cranial cruciate ligament rupture. Vet Comp Orthop Traumatol 2009; 22 (02) 83-86
• 18 De Sousa RJ, Knudsen CS, Holmes MA, Langley-Hobbs SJ. Quasi-isometric points for the technique of lateral suture placement in the feline stifle joint. Vet Surg 2014; 43 (02) 120-126
• 19 Hoots EA, Petersen SW. Tibial plateau leveling osteotomy and cranial closing wedge ostectomy in a cat with cranial cruciate ligament rupture. J Am Anim Hosp Assoc 2005; 41 (06) 395-399
• 20 De Sousa R, Sutcliffe M, Rousset N, Holmes M, Langley-Hobbs SJ. Treatment of cranial cruciate ligament rupture in the feline stifle. Biomechanical comparison of a standard fabella-tibial suture and lateral sutures placed between quasi-isometric points. Vet Comp Orthop Traumatol 2015; 28 (06) 401-408
• 21 Perry K, Fitzpatrick N. Tibial tuberosity advancement in two cats with cranial cruciate ligament deficiency. Vet Comp Orthop Traumatol 2010; 23 (03) 196-202
• 22 Allan RM. A modified Maquet technique for management of cranial cruciate avulsion in a cat. J Small Anim Pract 2014; 55 (01) 52-56
• 23 Retournard M, Bilmont A, Asimus E, Palierne S, Autefage A. Effect of tibial tuberosity advancement on cranial tibial subluxation in the feline cranial cruciate deficient stifle joint: An ex vivo experimental study. Res Vet Sci 2016; 107: 240-245
• 24 Kneifel W, Borak D, Bockstahler B, Schnabl-Feichter E. Use of a custom-made limb-press model to assess intra- and extracapsular techniques for treating cranial cruciate ligament rupture in cats. J Feline Med Surg 2018; 20 (04) 271-279
• 25 Koch L, Bockstahler B, Tichy A, Peham C, Schnabl-Feichter E. Comparison of extracapsular stabilization techniques using an ultrasonically implanted absorbable bone anchor (Weldix) after cranial cruciate ligament rupture in cats-an in vitro study. Animals (Basel) 2021; 11 (06) 1695
• 26 Scorcelletti M, Reeves ND, Rittweger J, Ireland A. Femoral anteversion: significance and measurement. J Anat 2020; 237 (05) 811-826
• 27 Kimura T, Kimura S, Okada J. et al. Retrospective radiographic study of degenerative joint disease in cats: Prevalence based on orthogonal radiograph front. Vet Sci 2020; 7: 138
• 28 Voss K, Karli P, Montavon PM, Geyer H. Association of mineralisations in the stifle joint of domestic cats with degenerative joint disease and cranial cruciate ligament pathology. J Feline Med Surg 2017; 19 (01) 27-35
• 29 Freire M, Robertson I, Bondell HD. et al. Radiographic evaluation of feline appendicular degenerative joint disease vs. Macroscopic appearance of articular cartilage. Vet Radiol Ultrasound 2011; 52 (03) 239-247
• 30 Cosenza G, Reif U, Martini FM. Tibial plateau levelling osteotomy in 69 small breed dogs using conically coupled 1.9/2.5 mm locking plates. A clinical and radiographic retrospective assessment. Vet Comp Orthop Traumatol 2015; 28 (05) 347-354
• 31 Freire M, Brown J, Robertson ID. et al. Meniscal mineralization in domestic cats. Vet Surg 2010; 39 (05) 545-552
• 32 Şen İ. Clinical and radiological evaluation of the treatment of cranial cruciate ligament rupture in cats with the musculus biceps femoris transposition technique. Acta Vet (Beogr) 2019; 69 (03) 300-311
• 33 Bilmont A, Retournard M, Asimus E, Palierne S, Autefage A. Effect of tibial plateau levelling osteotomy on cranial tibial subluxation in the feline cranial cruciate deficient stifle joint: An ex vivo experimental study. Vet Comp Orthop Traumatol 2018; 31 (04) 273-278
• 34 Comerford EJ, Tarlton JF, Wales A, Bailey AJ, Innes JF. Ultrastructural differences in cranial cruciate ligaments from dogs of two breeds with a differing predisposition to ligament degeneration and rupture. J Comp Pathol 2006; 134 (01) 8-16
• 35 Aicale R, Tarantino D, Maffulli N. Overuse injuries in sport: a comprehensive overview. J Orthop Surg Res 2018; 13 (01) 309
• 36 Stoneburner RM, Howard J, Gurian EM, Jones SC, Karlin WM, Kieves NR. Conservative nonsurgical treatment for cranial cruciate ligament disease can be an effective management strategy in cats based on validated owner-based subjective assessment in some cases. J Am Vet Med Assoc 2022; 260 (12) 1471-1474

Publication History

Received: 26 January 2025

Accepted: 09 April 2025

Article published online:
27 May 2025