Computed tomographic documentation of a comminuted fourth carpal bone fracture associated with carpal instability treated by partial carpal arthrodesis in an Arabian filly

OBJECTIVE: To report treatment of a unilateral comminuted fourth carpal bone (C4) fracture associated with carpal instability by partial carpal arthrodesis (PCA) of the middle carpal joint (MCJ) and carpometacarpal joint (CMCJ). STUDY DESIGN: Case Report. ANIMALS: An 8-month-old Arabian filly. METHODS: A C4 slab fracture was diagnosed radiographically; however, fracture comminution was conclusively diagnosed after computed tomographic (CT) imaging. PCA of the MCJ and CMCJ was performed with 2 narrow dynamic compression plates. RESULTS: PCA provided appropriate carpal stability and correct limb alignment immediately after surgery. Complete bony fusion with substantial carpal flexion and no lameness at walk or light trot was observed 8 months after surgery. CONCLUSIONS: Carpal CT was successfully used to define fracture configuration after standard radiographic examination failed to delineate comminution. PCA was selected because of joint instability and lateral carpal collapse of MCJ and CMCJ and can be successfully used to treat comminuted C4 slab fractures associated with carpal instability. Moderate MCJ osteoarthritis without radiocarpal joint involvement allows pain-free, substantial carpal flexion and thus, return to low-level pleasure riding may be possible. CLINICAL RELEVANCE: CT imaging may more adequately characterize traumatic carpal bone injury, particularly, when carpal bone fracture configuration cannot be determined on standard radiographs. Early PCA of the MCJ and CMCJ is an useful alternative to treat comminuted C4 slab fractures that cannot be reconstructed.     

Locking Compression Plates for Pancarpal Arthrodesis in a Thoroughbred Filly

Objective— To report treatment of a comminuted ulnar carpal (UC) bone fracture associated with carpal instability by pancarpal arthrodesis using 2 locking compression plates (LCP).
Study Design— Case report.
Animals— A 2-year-old Thoroughbred filly.
Methods— An UC fracture and luxation of the proximal row of carpal bones was diagnosed radiographically. Pancarpal arthrodesis was performed with 2 LCP positioned dorsolaterally and dorsomedially and centered over the carpus through a single skin incision. The filly was maintained in a full limb cast for 15 days, followed by a tube cast for 14 days, and subsequently a full limb bandage with caudal splint for 21 days.
Results— Two LCP provided appropriate carpal stability resulting in a pasture sound horse 6 months after surgery. The filly was discharged from the hospital 63 days after surgery, walking well with only a slight mechanical lameness.
Conclusion— Use of 2 LCP applied on the dorsomedial and dorsolateral aspect of the carpus can provide carpal stability for pancarpal arthrodesis.
Clinical Relevance— Excellent stability of the carpal joints can be achieved with 2 LCP.     

Surgical repair of radial carpal bone fractures in two racehorses

A 3-year-old Standardbred gelding (Case 1) and a 2-year-old Thoroughbred gelding (Case 2) were referred for surgical evaluation of a left radial carpal bone (RCB) fracture, sustained during training. Clinical findings at the time of initial examination included a palpable effusion within the left middle carpal joint in both horses and marked signs of pain and reduced range of motion on flexion of the affected carpus. In both horses, the RCB fracture was evident on the following radiographic views of the carpus: dorsolateral–palmaromedial oblique (30° off lateromedial) and flexed lateromedial. An additional loose wedge-shaped osteochondral fragment at the proximal articular surface of the RCB could be seen in Case 2. Both horses underwent surgical reduction and repair of the fracture between 1 and 2 days following the initial injury, which consisted of arthroscopic removal of any intra-articular osteochondral fragments, and arthroscopic assisted-interfragmentary compression via a standard dorsomedial and dorsolateral approach to the antebrachiocarpal joint (ACJ) and middle carpal joints (MCJ). The two horses returned to function as racehorses, 6 months (Case 1) and 16 months (Case 2) after surgery. The RCB is a relatively uncommon site for large carpal fractures in horses. The clinical presentation and findings from this report were similar to that of third carpal bone (C3) slab fractures, confirming that surgical repair is indicated in selected cases of RCB fractures.     

Partial carpal and pancarpal arthrodesis in the dog: a review of 50 cases

Fifty-six carpal arthrodeses were carried out in 50 dogs. Six of these had bilateral arthrodeses. A dynamic compression plate (DCP; Straumann Great Britain Ltd), placed on the dorsal aspect of the carpus, was used for fixation in all cases. The main indication for pancarpal arthrodesis was a hyperextension injury of the radiocarpal joint. Forty-three pancarpal arthrodeses were performed in 40 dogs (a bilateral procedure was performed in three). Hyperextension injuries of the intercarpal and carpometacarpal joints were treated by partial carpal arthrodesis in 10 dogs; three of these had bilateral procedures. Seventy-four per cent of dogs treated by pancarpal arthrodesis regained full limb function. Only 50 per cent of cases treated by partial carpal arthrodesis had a similar result.     

Radiographic and clinical features of carpal varus associated with chronic sprain of the lateral collateral ligament complex in 10 dogs.

Lameness associated with carpal varus deformity was recognised in 10 dogs, eight of which were Dobermann Pinschers. The dogs had a mean age of seven years and nine months. Carpal varus was usually bilateral with concurrent carpal hyperflexion and pronation. Carpal varus was present prior to the onset of lameness in four cases. With stress radiography the median angle of varus deviation in all carpi was 14.6 degrees , and an increase in the size of the ulnar /ulnar carpal bone joint space was seen in six of the seven dogs. Radiographic changes included: enthesophyte formation at the proximolateral aspect of metacarpal V, periarticular soft tissue swelling, especially lateral, bone proliferation at the carpometacarpal joint I and enthesophyte formation at metacarpophalangeal joint V. Four dogs were admitted for problems other than carpal varus and lameness was not treated. Five dogs were treated with nonsteroidal anti-inflammatory drugs, but lameness was not completely resolved and became exacerbated with exercise. One dog was successfully treated by pancarpal arthrodesis.     

Partial Carpal Arthrodesis for Third Degree Carpal Sprains: A Review of 45 Carpi

The efficacy of partial carpal arthrodesis was evaluated retrospectively in 39 dogs (45 carpi) with severe sprains of the middle carpal joints, the carpometacarpal joints, or both. The carpometacarpal joint was the most frequently injured joint. Jumping or falling from heights was the cause of injury in 49% of these animals. Of the 25 owners who responded to a mailed questionnaire (mean follow-up, 32 months), all stated their animal had improved or greatly improved after partial carpal arthrodesis and all were pleased or very pleased with the final surgical result. Hyperextension persisted in 11% of the cases and degenerative joint disease of the antebrachiocarpal joint was present in 15.5% of the cases. No dogs with partial carpal arthrodesis required panarthrodesis at a later date.     

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.     

Avascular necrosis of the canine radial carpal bone: a condition analogousto Preiser's disease?

An eight‐year‐old male neutered Staffordshire bull terrier was presented for investigation of right forelimb lameness of 14 months’ duration. Radiography showed mottled osteolysis of the right radial carpal bone. Histopathology of the bone demonstrated replacement of healthy bone with granulation tissue suggestive of ischaemic necrosis. Lameness resolved following pancarpal arthrodesis. In humans, Preiser's disease is a condition in which idiopathic ischaemic necrosis of the scaphoid bone, the equivalent of the canine radial carpal bone, occurs. This disease may be analogous to the presentation seen in this case. To the authors’ knowledge, this is the first report of such a condition in a dog.     

Bilateral distal radial epiphysectomy and pancarpal arthrodesis for correction of complex carpal deformities in an American Miniature horse

A 9‐day‐old American Miniature horse was referred for evaluation and treatment of congenital bilateral carpal deformities. Clinical examination revealed a combination of flexural, angular and rotational deformities affecting both carpi. Radiographic evaluation of both forelimbs revealed malformation of the distal radial epiphysis accompanied by flexural contracture and external rotation of the limb distal to the antebrachial carpal joint. Conservative therapy was attempted with splints and bandages and failed to result in improvement. Surgical intervention was elected and a bilateral distal radial epiphysectomy and pancarpal arthrodesis performed. Fourteen months later the mare was turned out to pasture and ambulating well.     

The use of veterinary cuttable plates for carpal and tarsal arthrodesis in small dogs and cats

The objective of the study was to evaluate, retrospectively, carpal and tarsal arthrodesis in small dogs and cats by using veterinary cuttable plates in 6 animals and comparing those with arthrodesis stabilized with other implants in 9 animals. Veterinary cuttable plates were used for 1 pancarpal, 2 partial tarsal, and 3 pantarsal arthrodeses. Other implants were used to stabilize 1 pancarpal, 6 partial tarsal, and 2 pantarsal arthrodeses. In the veterinary cuttable plates group, complications included 2 cases with pressure sores and 1 case with screw loosening. One animal was lost to follow-up and 4 of the remaining 5 were always weight-bearing. In the other group, there were 2 cases with pressure sores, 1 case with dermatitis, and 2 cases with pin migration. Six out of 9 animals were always weight-bearing. The use of veterinary cuttable plates appears to be a suitable option with a good clinical outcome.     

Treatment of a second carpal bone fracture by removal under ultrasonographic guidance in a horse

OBJECTIVE: To report an unusual 2nd carpal bone (C2) slab fracture and its treatment, using an ultrasonographically assisted, minimally invasive arthrotomy technique, for fragment removal. STUDY DESIGN: Case report. ANIMALS: An 11-year-old crossbred Warmblood gelding. METHODS: A bone fragment, spanning the height of C2, identified on the palmaromedial aspect of C2 was demarcated intraoperatively using ultrasonographically guided needles and removed by arthrotomy. RESULTS: Fracture fragment removal was achieved using a small, ultrasonographically guided arthrotomy. The horse has become sound after treatment and returned to the previous level of pleasure riding activity. CONCLUSIONS: Perioperative ultrasonography was used to delineate and facilitate removal of an unusual slab fragment of C2, through a minimally sized arthrotomy. Despite the presence of pancarpal osteoarthritis and partial involvement of the medial collateral ligament, the prognosis appeared to be satisfactory for this pleasure riding horse. CLINICAL RELEVANCE: Ultrasonographic guidance may be used to optimize the approach to C2 articular bony fragments that may not be observed using arthroscopy.     

Treatment with rhBMP-2 of extreme radial bone atrophy secondary to fracture management in an Italian Greyhound

rhBMP-2 solution on a collagen sponge was placed along the diaphysis of an atrophicradius, which had a history of recurring fractures. Two months after rhBMP-2 treatment, new mineralized bone was present, which significantly increased the diameter of the radius and allowed the removal of the external skeletal fixator (ESF). Due to carpo-metacarpal joint compromise, a pancarpal arthrodesis was performed seven months later. At follow-up evaluation two years later the dog was only very mildly lame.     

Femoral Fracture Repair Using a Locking Plate Technique in an Adult Captive Polar Bear (Ursus Maritimus)

Objective— To report successful femoral fracture repair in a polar bear. Study Design— Case report. Animals— Female polar bear (Ursus maritimus) 5 years and ～250 kg. Methods— A closed, complete, comminuted fracture of the distal midshaft femur was successfully reduced and stabilized using a compression plating technique with 2 specialized human femur plates offering axial, rotational, and bending support, and allowing the bone to share loads with the implant. Postoperative radiographs were obtained at 11.5 weeks, 11 months, and 24 months. Results— Bone healing characterized by marked periosteal reaction was evident at 11 months with extensive remodeling evident at 24 months. No complications were noted. Conclusions— Distal mid shaft femoral fracture was reduced, stabilized, and healed in an adult polar bear with a locking plate technique using 2 plates. Clinical Relevance— Previously, femoral fractures in polar bears were considered irreparable. Use of 2 plates applied with a locking plate technique can result in successful fracture repair despite large body weight and inability to restrict postoperative activity.     

Prospective evaluation of pancarpal arthrodesis for carpal injuries in working dogs in New Zealand,using dorsal hybrid plating

Abstract

AIM: To determine whether working dogs in New Zealand with carpal injuries and treated with unilateral pancarpal arthrodesis (PCA), using a dorsal hybrid-plating method, are able to return to satisfactory working ability.

METHODS: Fourteen working dogs presented to the Veterinary Specialist Group (VSG) and the Massey University Veterinary Teaching Hospital (MUVTH) with carpal injuries were prospectively treated using dorsal hybrid plating. Dogs were eligible if actively involved in farm, hunting or police work. Dogs had a standardised PCA surgical procedure performed, and similar instructions for post-operative care were provided. Dogs were re-evaluated clinically and radiographically at 6 weeks, 6 months, and 12 months after surgery. A questionnaire was completed by 12 owners, to assess each dog's working ability.

RESULTS: Twelve months following arthrodesis, 10/12 (83%) dogs could perform most or all duties normally. Eleven owners (92%) reported that the result of the surgery met their expectations, and nine owners (75%) were very satisfied with the outcome of the surgery. No owners were disappointed or very disappointed with the surgical outcome. Post-operative complications requiring surgical removal of the implant occurred in three (25%) dogs.

CONCLUSIONS: Unilateral PCA using a standardised surgical procedure and dorsal hybrid plating of carpal injuries has a good prognosis for working dogs in New Zealand to return to work.

CLINICAL RELEVANCE: These results may allow veterinarians to provide a more accurate prognosis to owners of working dogs that have debilitating carpal injury     

Diagnosis and treatment of carpometacarpal desmopathy in a horse

A 9‐year‐old Warmblood gelding underwent magnetic resonance (MR) imaging of the carpal and proximal metacarpal regions for evaluation of prolonged right forelimb lameness. Magnetic resonance findings were indicative of desmopathy of the right lateral carpometacarpal ligament and the interosseous ligament between the third and fourth metacarpal bones. Based on the MR findings and lack of response to conservative therapy, surgery using a drilling technique was performed to facilitate fusion of the right carpometacarpal joint. After surgery and a 6‐month rest and rehabilitation programme, the horse returned to soundness. This case report describes a unique combination of lateral carpal/proximal metacarpal soft tissue injuries that resulted in prolonged lameness and were treated with facilitated arthrodesis of the carpometacarpal joint. These soft tissue injuries should be considered as a differential diagnosis in horses with lameness localised to the proximal metacarpal/distal carpal region.     

Pancarpal Arthrodesis in the Dog: A Review of Forty-five Cases

This report describes an open surgical technique for pancarpal arthrodesis and its efficacy in 45 canine cases. Indications for carpal arthrodesis include hyperextension injuries, severe fracture/luxations, end-stage arthritis, and selected neurologic deficits. Chronic joint instability was the major indication for surgery (76%). Degenerative joint disease (18%) and neurologic deficits (6%) accounted for the other cases. In a subjective owner survey, 97% of the owners reported that their animals' gait improved following arthrodesis, and 74% stated that their animals walked and ran normally.     

Minimally invasive proximal interphalangeal joint arthrodesis using a locking compression plate and tissue engineering in horses: A pilot study

This pilot study assessed the efficacy of 2 minimally invasive techniques for proximal interphalangeal (PIP) joint arthrodesis in horses. The PIP joints of both forelimbs (n = 6) were stabilized with locking compression plates (LCP) using a minimally invasive technique (LCP technique). Subsequently, for 1 randomly selected PIP joint of each horse, surgical drilling (SurD) was performed and tissue engineering (TE) was applied (LCP/SurD/TE technique). Minimally invasive PIP joint arthrodesis with LCP demonstrated low postoperative infection rates. Gross and histological evaluations revealed considerable destruction of the articular cartilage in the LCP/SurD/TE-treated joints. In contrast, almost no destruction of the cartilage was observed in the LCP-treated joints. Our results suggest that the LCP technique alone is not sufficient for PIP joint arthrodesis and that the LCP/SurD/TE technique may be useful for PIP joint arthrodesis in horses.     

Spontaneous bilateral ankylosis of the carpometacarpal joint in a Paint Horse

An 8‐year‐old Paint Horse gelding was evaluated for a persistent left forelimb lameness (grade 4/5), with a hard swelling at the dorsomedial aspect of the carpometacarpal joint, due to osteoarthritis. Previous systemic and local anti‐inflammatory therapy had only a temporary effect. Partial carpal arthrodesis was suggested, but the owner elected for conservative treatment. The horse was confined to a small paddock and received phytotherapeutic supplementation with Harpagophytum procumbens. The lameness gradually resolved but a similar hard swelling developed on the right carpus. Radiographic follow‐up 1.5 years later revealed a spontaneous bilateral ankylosis of the carpometacarpal joint.     

Treatment of Carpometacarpal Osteoarthritis by Arthrodesis in 12 Horses

Objective— To evaluate arthrodesis as a treatment for carpometacarpal joint osteoarthritis (CMC‐OA). Study Design— Case series. Animals— Horses (n=12) with CMC‐OA. Methods— Arthrodesis was facilitated by insertion and fanning of a drill bit into the CMC joint at several (3–5) locations in 15 limbs. Follow‐up radiographs were obtained for 7 horses (9 limbs). Outcome was determined by telephone survey of owners based on postoperative pain, return to use, appearance of the limb, and success of treatment. Results— Postoperative pain was slight or moderate in 10 of 12 (83%) horses during the first 30 days, and 11 of 12 (92%) horses were markedly improved by 6 months and capable of returning to work. Radiographically 6 CMC joints had a bony ankylosis at follow‐up whereas 3 did not (mean 8.7 months). On long‐term follow‐up (mean 28.6 months) all horses had reduced severity of lameness, 10 of 12 (83%) were considered “sound,” 8 (67%) returned to their original activity, and all owners considered arthrodesis highly successful as a treatment. Conclusion— A drilling technique that produced CMC arthrodesis, allowed most horses to return to their original activity and was considered successful by all clients. Clinical Relevance— Arthrodesis of the CMC joint should be considered a treatment option for CMC‐OA.     

Evaluation of a minimally invasive arthrodesis technique for the carpometacarpal joint in horses

Objective: To evaluate a minimally invasive technique for arthrodesis of the carpometacarpal (CMC) joint in horses. Study Design: Experimental study. Animals: Healthy horses (n=6). Methods: A 5.5 mm, 3‐drill tract arthrodesis technique was evaluated in 1 randomly selected CMC joint in each of 6 normal horses. Peak vertical ground reaction force (GRF) values were recorded before surgery and at 6, 8, and 12 months thereafter. Radiographic and clinical lameness scores were assigned at regular intervals until 12 months after surgery when the horses were euthanatized. Gross and histologic examinations were performed on the treated CMC joints. Results: After surgery, all horses were lame. Clinical resolution of lameness occurred in 2 by 12 months. Mean peak vertical GRF values significantly differed between treated and nontreated limbs at all recorded time points after surgery. Radiographic scores significantly differed from day 0 at all times after surgery, but did not change significantly after 4 months. Intraarticular bony ankylosis only occurred in 2 horses, based on gross, histologic, and microradiographic examination of sagittal sections of the operated CMC joints. Conclusion: The 5.5 mm, 3‐drill tract arthrodesis technique was considered successful in only 2 of 6 normal CMC joints treated. Greater articular damage may be necessary to achieve arthrodesis in normal horses. Better results may be achieved by technique modification or in horses affected by CMC osteoarthritis.