Repair of chronic rupture of the insertion of the gastrocnemius tendon in the dog using a polyethylene terephthalate implant. Early clinical experience and outcome.

OBJECTIVES: Chronic degeneration of the gastrocnemius tendon results in scar tissue formation at the insertion of the tendon, and detachment from the calcaneus. In severe cases, excision of this tissue makes repositioning of the tendon to the calcaneus extremely difficult. A polyethylene terephthalate implant, used to aide repair by bridging gaps and allowing tissue ingrowth, was evaluated. METHODS: In this retrospective study, clinical records were evaluated to assess long-term outcomes and complications. The surgical technique is also described. The implant was sutured proximally into the gastrocnemius at the myotendinous junction, and secured into the calcaneus using an interference screw. RESULTS: The implant was used in 10 patients; of which seven returned to full function. Major complications, due to infection, were identified in two of the 10 patients. Minor complications occurred in five of the 10 patients. These were associated with external coaptation in three of the patients in the immediate postoperative period. One minor infection was reported. These all resolved without further complication. Long-term outcome was available in eight patients, with six of these eight dogs returning to normal exercise. CLINICAL SIGNIFICANCE: This implant may be suitable for use in canine patients with severe gastrocnemius tendon degeneration. Ongoing evaluation is warranted.

Complications of lateral plate fixation compared with tension band wiring and pin or lag screw fixation for calcaneoquartal arthrodesis. Treatment of proximal intertarsal subluxation occurring secondary to non-traumatic plantar tarsal ligament disruption in dogs.

OBJECTIVE: To compare complication rates and the outcomes of these complications after lateral plate fixation with figure-of-eight tension-band-wire and pin or lag screw fixation for arthrodesis of the calcaneoquartal joint, following non-traumatic disruption of the plantar tarsal ligament in dogs. METHODS: Data were collected retrospectively from five UK referral centres. Diplomate specialists and their residents performed all procedures. Referring veterinarians were contacted for long-term follow-up. RESULTS: Seventy-four procedures were undertaken in 61 dogs. There were 58 arthrodeses in the lateral plate group (Plate), nine in the pin and tension-band-wire group (Pin), and seven in the lag screw and tension-band wire-group (Screw). Compared to Plate (17%), further surgical intervention was required more frequently following Pin (56%, OR = 3.2) or Screw (43%, OR = 2.5) fixation. Clinical failure of arthrodesis occurred less frequently with Plate (5%) compared with Screw (43%, OR = 8.6) and Pin fixation (22%, OR = 4.4). Cases managed with external coaptation postoperatively were more likely to suffer from postoperative complications (OR = 2.2). CLINICAL SIGNIFICANCE: Lateral plating was associated with fewer postoperative complications than pin and tension-band-wire fixation for arthrodesis of the calcaneoquartal joint in dogs with non-traumatic disruption of the plantar tarsal ligament.

Long-term results of transarticular pinning for surgical stabilisation of coxofemoral luxation in 20 cats.

OBJECTIVES: The objective of this study was to describe initial and long-term results of open reduction and transarticular pinning for treatment of coxofemoral luxations in cats. METHODS: Cats were treated by open reduction and transarticular pinning for coxofemoral luxation over a five year period at two institutions. Follow-up assessment included orthopaedic examination, radiography and owner questionnaires. RESULTS: Twenty cats were included in the study (14 males and six females). One cat was affected bilaterally. Mean time to follow-up was 21 months. Seventeen joints were stabilised with a 1.6 mm pin, three with 2.0 mm pins and a 1.2 mm pin was used in the remaining joint. An Ehmer sling was not utilised in any case. All transarticular pins except one were removed (mean 3.5 weeks), with all hips still in reduction The overall success rate was 77 per cent, with two reluxations and one resorbed femoral head noted on radiographs of 13 joints followed long term. All 20 owners reported good to excellent long-term functional outcome for their cats. CLINICAL SIGNIFICANCE: Results from this study indicate that transarticular pinning for stabilisation of coxofemoral luxation in cats can provide a good long-term outcome without sacrificing the integrity of the coxofemoral joint.

Use of biochemical markers of osteoarthritis to investigate the potential disease-modifying effect of tibial plateau levelling osteotomy.

OBJECTIVES: To evaluate the hypothesis that the concentration of the 1/20/5D4 epitope of keratan sulphate, cartilage oligomeric matrix protein and total sulphated glycosaminoglycans in synovial fluids from dogs with cranial cruciate ligament disease would be affected by tibial plateau levelling osteotomy. In addition, to evaluate the hypothesis that medial meniscal release or meniscal injury would alter the expression of these candidate biomarkers. METHODS: Forty-one dogs with naturally occurring cranial cruciate ligament disease were recruited prospectively. Synovial fluids were collected from the index joint before surgery and six weeks and six months postsurgery. Following tibial plateau levelling osteotomy, synovial fluids were assayed for 1/20/5D4 epitope of keratan sulphate and cartilage oligomeric matrix protein concentration using an inhibition ELISA and for sulphated glycosaminoglycans using a direct dye-binding assay. RESULTS: The sulphated glycosaminoglycans ratio did not change significantly during the study. Medial meniscal injury at entry was associated with lower concentrations of synovial fluid cartilage oligomeric matrix protein (P<0.05, unpaired t test). There was no association between medial meniscal release and the changes in marker concentrations, either from 0 to six weeks or 0 to six months. CLINICAL SIGNIFICANCE: Tibial plateau levelling osteotomy did not significantly alter the expression of the named candidate biomarkers. These findings reflect the limited nature of the arthrotomy or indicate that tibial plateau levelling osteotomy does not influence the progression of osteoarthritis (OA). From these studies, there is no evidence that tibial plateau levelling osteotomy affects cartilage metabolism.

Progression of osteoarthritis following TPLO surgery: a prospective radiographic study of 40 dogs.

The aim of this prospective study was to assess the progression of osteoarthritis following tibial plateau levelling osteotomy (TPLO) surgery. Osteoarthritis was monitored radiographically by means of an osteophyte scale on entry to the study, and at six weeks and six months following surgical intervention. Forty dogs were recruited to the study. At each visit, animals were assessed clinically, radiographically, by force platform analysis and by synovial fluid sampling. The radiographic data is the subject of this report. A significant increase in mean osteophyte score was noted between the entry and six-month examination time point. This increase in the mean osteophyte score was due to the increased score recorded in 16 dogs. However, in the majority of dogs, there was no progression of osteophytosis during the course of this study.

Vascular hamartoma within the flexor muscles of the left carpus in a dog.

A three-year-old male bearded collie was presented with a history of left thoracic limb lameness and a fluctuant non-painful swelling within the flexor tendons of the left carpus. Investigations included ultrasonography, laboratory analysis of fluid aspirated from the lesion and positive contrast radiography. Treatment involved surgical resection of the lesion from the local flexor muscles of the carpus. Histologically, the resected tissue was considered to represent a vascular hamartoma associated with the pronator quadratus muscle.

Metacarpal fractures associated with pancarpal arthrodesis in dogs.

OBJECTIVE: To report the prevalence of third metacarpal bone fractures after dorsal plating for pancarpal arthrodeses in dogs and to identify predisposing factors. STUDY DESIGN: Retrospective clinical study. ANIMALS: Fifty-four client-owned dogs. METHODS: Pancarpal arthrodesis was performed using dorsally applied 2.7- or 3.5-mm bone plates. Medical records and radiographs were retrospectively evaluated to identify those dogs with metacarpal bone fractures after pancarpal arthrodesis and to determine the angle of arthrodesis, the percentage of the third metacarpal bone covered by the bone plate, and the percentage width of the bone occupied by the screw. Radiological evidence of arthrodesis at follow-up examination 6 weeks postoperatively was recorded. Long-term results were obtained by telephone follow-up with the owners. All lame dogs were evaluated clinically and radiographically. RESULTS: Metacarpal fractures occurred in 6 of 54 dogs. One of these dogs had a stress fracture of the third metacarpal 10 months after implant removal and was not included in the statistical analysis. Fractures occurred through the distal screw hole in four dogs and involved two metacarpal bones (III and IV) in two dogs. The median ratio of bone screw diameter-to-metacarpal bone diameter was the same for dogs with metacarpal bone fractures and those with no fractures (44%), and the median angles of arthrodesis were 8 degrees and 7 degrees. These values were not statistically significant. The percentage length of the metacarpal bone covered by the plate was 53% (no fracture) compared with 46% (fracture), and this difference was statistically significant (P = .035). CONCLUSIONS: Screw diameter was not implicated as a predisposing factor for metacarpal bone fracture in dogs undergoing pancarpal arthrodesis using a dorsally applied dynamic compression plate. The length of the metacarpal bone covered by the bone plate did affect the frequency of metacarpal fracture, with fewer fractures occurring when greater than 53% of the bone length was covered by the dynamic compression plate. CLINICAL RELEVANCE: When performing pancarpal arthrodesis with a dorsally applied bone plate, it is recommended that at least 50% of the length of the third metacarpal bone should be covered by the plate.

Arthrodesis of the tarsometatarsal joint using a laterally applied plate in 10 dogs.

The efficacy of tarsometatarsal arthrodesis using a laterally applied plate was evaluated retrospectively in 10 dogs (11 joints). Arthrodesis was performed to manage a tarsometatarsal subluxation in two hocks; in the other cases, the tarsometatarsal subluxation was accompanied by tarsal or metatarsal fractures. The average period to referral was 15 days and all dogs had been managed with previous external coaptation of the affected limb. Arthrodesis was achieved in all the joints following initial surgery. Implant removal was indicated in three dogs which remained intermittently lame. Implants were left in situ in the remaining seven dogs. After an average follow-up period of 28 months, all dogs had resumed normal activity. Seven dogs were reported to be completely sound, one was stiff after rest following vigorous exercise and two had an intermittent mild lameness following strenuous exercise.

Repair of femoral trochanteric osteotomy in the dog.

The records and radiographs of 24 dogs that underwent femoral trochanteric osteotomy repair were reviewed. Osteotomy repair was performed with either a pin and tension band wire or a lag screw technique. Significant clinical complications associated with the osteotomy were identified in one dog (4 per cent) six weeks after surgery, although abnormal radiographic changes were evident in 15 dogs (62 per cent). The method of repair did not influence healing and there were comparable radiographic complication rates. It is concluded that femoral trochanteric osteotomy is not associated with significant clinical problems, despite a high incidence of abnormal radiographic findings.

Radiation hazards from horses undergoing scintigraphy using technetium-99m.

This paper quantifies the extent of the radiation hazard to personnel from horses undergoing scintigraphy using technetium99m methylene diphosphonate (99Tcm-MDP). From the data produced it is possible to derive safe working protocols which are comfortably within the legislated limits for whole body doses as set out in the Ionising Radiations Regulations 1985. Measurements were made of the surface and environmental activities which result from individuals undergoing scintigraphic evaluation and also from urine contaminated bedding. The use of both high and low activities in the assessment of the radiation hazard to personnel and owners is considered.