Evaluation of the Clavicle Hook Plate for Treatment of Acromioclavicular Joint Dislocation: A Cadaveric Study.

OBJECTIVES: To describe surgical technique for proper placement of the clavicle hook plate, determine whether there is subacromial impingement caused by hook plate fixation, and evaluate the mechanical strength of the clavicle hook plate construct. METHODS: Eight fresh-frozen cadaveric shoulders with a mean age of 48 years (range, 37-69) were used. Open reduction and internal fixation of simulated Rockwood type V AC joint dislocation was performed with the clavicle hook plate. Three-dimensional computed tomography studies and arthroscopic evaluation were performed with the glenohumeral joint in different orientations to assess the position of the hook plate relative to relevant joint structures. The clavicle was then superiorly loaded to mechanical failure. RESULTS: Computed tomography evaluations showed no contact between the humerus and the hook plate. Distance between the greater tuberosity and hook plate ranged from 14 to 31 mm with maximal shoulder forward flexion and 8.1-25.4 mm with maximal shoulder abduction. Arthroscopic evaluation of the subacromial space demonstrated that with maximal abduction/forward flexion, there was abutment of the rotator cuff with the hook plate in 6 of 8 specimens. In mechanical testing, mean failure load was determined to be 1011 N (range, 380-1563 N). Failure mechanisms included acromion fracture (4), slippage of the hook under acromion (3), and distal clavicle fracture (1). CONCLUSIONS: This study demonstrates that the clavicle hook plate reduces AC joint dislocation or distal clavicle fractures anatomically, has supra-physiologic mechanical strength, does not cause bony impingement, and exhibits rotator cuff impingement only with maximal abduction/forward flexion of the shoulder.

Relative risk factors for requirement of blood transfusion after total hip arthroplasty.

One thousand thirty-five total hip arthroplasty (THA) cases were retrospectively reviewed, and the number and type (autologous and allogenic) of postoperative units of blood transfused were analyzed with respect to pre-, intra-, and postoperative variables. The most significant and consistent predictors of a blood transfusion after THA were advanced age and the use of low-molecular-weight heparin for deep venous thrombosis prophylaxis. Our recommendations for predonation are 1 unit for THA patients younger than 75 years if hemoglobin is 130 g/dL or greater and 2 units or a combination of 1 unit of predonated blood and 1 unit of directed or banked blood for THA patients older than 75 years.

Heparin-induced thrombocytopenia and thrombosis.

Heparin-induced thrombocytopenia (HIT) and heparin induced thrombocytopenia with thrombosis (HITT) ar rare complications associated with use of unfractionate heparin (UFH) or low-molecular-weight heparin (LMWH) HIT is a benign clinical condition characterized by a mil drop in platelet count with no clinical significance. HIT is an immune-mediated reaction associated with a wide spread "hypercoagulable" state resulting in arterial an venous thrombosis. There is a higher incidence of HIT with UFH use than with LMWH use. Orthopedic surger patients are at higher risk for developing HITT than are patients who receive prophylactic heparin for cardiovascular surgery or medical reasons. Therapy for patients suspected of having HITT should begin with immedi ate discontinuation of heparin in any form followed by pharmacologic inhibition with thrombin (e.g., recombinant hirudin [lepirudin], argatroban, danaparoid sodium).

Intramedullary nailing of the lower extremity: biomechanics and biology.

The intramedullary nail or rod is commonly used for long-bone fracture fixation and has become the standard treatment of most long-bone diaphyseal and selected metaphyseal fractures. To best understand use of the intramedullary nail, a general knowledge of nail biomechanics and biology is helpful. These implants are introduced into the bone remote to the fracture site and share compressive, bending, and torsional loads with the surrounding osseous structures. Intramedullary nails function as internal splints that allow for secondary fracture healing. Like other metallic fracture fixation implants, a nail is subject to fatigue and can eventually break if bone healing does not occur. Intrinsic characteristics that affect nail biomechanics include its material properties, cross-sectional shape, anterior bow, and diameter. Extrinsic factors, such as reaming of the medullary canal, fracture stability (comminution), and the use and location of locking bolts also affect fixation biomechanics. Although reaming and the insertion of intramedullary nails can have early deleterious effects on endosteal and cortical blood flow, canal reaming appears to have several positive effects on the fracture site, such as increasing extraosseous circulation, which is important for bone healing.

Blisters associated with lower-extremity fracture: results of a prospective treatment protocol.

OBJECTIVES: To evaluate patient outcomes after treatment of lower-extremity fractures associated with blister formation and to assess complications after soft-tissue treatment using a prospective protocol. DESIGN: Retrospective evaluation of prospectively collected data. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: Between September 1999 and September 2003, 47 patients who had sustained a closed lower-extremity fracture with early development of fracture blisters in the zone of injury were followed. Blisters were characterized as either avoidable or unavoidable with respect to surgical incisions, and characteristics such as number, size, blood filled or clear filled, and the presence of an intact roof were documented. INTERVENTION: All blisters were unroofed, and antibiotic cream (silver sulfadiazine, Silvadene, King Pharmaceuticals Inc.) was applied twice daily until the blister bed had re-epithelialized. MAIN OUTCOME MEASUREMENTS: Fracture union and the development of wound or skin complications. Patient satisfaction with the cosmetic outcome of the treatment regimen was assessed through telephone survey at 23-month minimum follow-up. RESULTS: Twenty-eight patients presented with a single blister, and 19 had multiple blisters. Blister size averaged 9.7 cm. Twenty-two patients had blood-filled blisters, 20 had clear-filled blisters, and five had a combination of the two. Fracture patterns included 17 ankle fractures (OTA 44), 13 tibial plateau fractures (OTA 41), five tibial-shaft fractures (OTA 42), eight calcaneus fractures (OTA 45), and four pilon fractures (OTA 43). Mean delay in definitive surgical care was 7.7 days (range 0 to 20 days). The average delay of surgery for ankle fractures was 6 days (range 0 to 18 days), which was significantly less than the delay for calcaneus fractures (12 days, range 4 to 19 days, P < 0.02) and tibial plateau fractures (11 days, range 0 to 20 days, P < 0.02). Thirty-seven of the 45 patients (82.3%) available for follow-up at a mean of 27 weeks (range 14 to 35) had an uncomplicated postoperative course, and fracture union was achieved in 43 of 45 cases (95.6%). The soft-tissue complication rate associated with the standardized treatment regimen was 13.3% (6/45 cases), with three cases of minor soft-tissue breakdown, one superficial infection, and two major complications directly related to the presence of fracture blisters. Both major complications involved full-thickness skin breakdown occurring directly at the base of fracture blisters in patients with diabetes. The skin breakdown required further surgery in both cases. Including the two patients who developed nonunion, the overall complication rate for the treatment cohort was 17.7% (8/45 cases). At a mean follow-up of 51.9 months (range 23 to 73), three patients in the cohort had expired. Of the 42 patients available for evaluation, 28 patients (67%) were reachable for a telephone survey to assess satisfaction with the outcome of the fracture and soft-tissue management. Patients rated their satisfaction with the cosmetic appearance of their lower extremities after the standardized treatment regimen on a scale of 1 to 10 (with 10 representing very satisfied), with a mean of 9.07 (range 5 to 10). Six patients reported scarring at the sites of previous fracture blisters, all of which occurred after blistering of the blood-filled subtype. The presence of scarring significantly decreased patient satisfaction with cosmesis and overall treatment (P < 0.0001 and P < 0.01, respectively). CONCLUSIONS: Treatment of fracture blisters with a silver sulfadiazine (Silvadene) regimen proved to be successful in minimizing soft-tissue complications by promoting re-epithelialization in all nondiabetic patients. At long-term follow-up, patients were generally satisfied with the cosmetic outcome of the treatment regimen. Postoperative scarring, which was more common with blood-filled blisters, significantly impacted patient satisfaction. We urge caution when planning to make a surgical incision around an area of both full-thickness (blood-filled) and partial-thickness (clear-filled) fracture blisters in diabetic patients because the zone of injury might extend beyond the borders of the fracture blister.

Midterm results of primary total knee arthroplasty using a dished polyethylene insert with a recessed or resected posterior cruciate ligament.

Use of a dished polyethylene insert in 114 total knee arthroplasties, all with the posterior cruciate ligament resected or recessed, was retrospectively studied. Patients were evaluated at a mean follow-up of 8.3 years. Mean range of motion increased from 92 degrees to 111 degrees . Mean Knee Society pain and function scores increased from 35.2 and 39.7 to 91.3 and 74.7, respectively. WOMAC scores improved significantly in each category evaluated, including pain, stiffness, and physical function. Kaplan-Meier survivorship was 95% at 10 years (95% confidence interval, 82%-99%). The use of a dished polyethylene insert in primary total knee arthroplasty provides good to excellent midterm results regardless of whether the posterior cruciate ligament is recessed or sacrificed.

Total hip arthroplasty in a patient with contralateral hemipelvectomy.

Total hip arthroplasty has evolved in regard to surgical technique, implant design, and long-term survivorship over the last several decades with excellent clinical results. Owing to these improvements, indications for surgery have expanded to include a greater variety of patients. We present the case of a 62-year-old man who underwent total hip arthroplasty 39 years after contralateral hemipelvectomy. The importance of an appropriate preoperative plan in regard to patient positioning and postoperative protocol is addressed. Our patient was informed that data concerning his case would be submitted for publication.

A comparison of immediate postreduction splinting constructs for controlling initial displacement of fractures of the distal radius: a prospective randomized study of long-arm versus short-arm splinting.

PURPOSE: To compare, in a prospective, randomized manner, the sugar tong splint with a short-arm radial gutter splint in terms of patient satisfaction and the ability to maintain reduction of distal radius fractures. METHODS: A total of 118 patients with displaced distal radius fractures were enrolled; 85 patients (85 fractures) were available for follow-up evaluation and were included in the study population. There were 26 men and 59 women with a mean age of 64 years. Thirty-eight fractures were immobilized in a short-arm radial gutter splint and 47 in a sugar tong splint. Forty fractures had a stable pattern and 45 had an unstable fracture pattern. The initial patient follow-up examination occurred a mean of 8 days after splint application. RESULTS: A total of 33 fractures showed loss of fracture reduction at the initial follow-up evaluation. Sixteen of 38 fractures immobilized with the radial gutter splint displaced, whereas displacement was seen in 17 of 47 fractures immobilized with a sugar tong splint; this difference was not significant. When the splint constructs were evaluated based on fracture stability no differences were found between the splints' ability to maintain fracture reduction in both stable and unstable displaced fractures. Patients in the short-arm radial gutter splint group had significantly better Disabilities of the Arm, Shoulder, and Hand scores than those patients whose fractures were immobilized with a sugar tong splint. CONCLUSIONS: Both the sugar tong splint and the short-arm radial gutter splint had comparable performance in maintaining the initial reduction of distal radius fractures, with the short-arm splint tolerated better by patients. Based on our study we recommend the use of a short-arm radial gutter splint for initial immobilization of displaced distal radius fractures. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic, level II.

Orthopedic surgical management of hip and knee involvement in patients with juvenile rheumatoid arthritis.

Juvenile rheumatoid arthritis is the most common arthritic disease of childhood and a leading cause of childhood disability, affecting an estimated 300,000 US children and adolescents aged < or =16 years. Approximately 10% to 30% of patients experience functional deficits resulting from both the articular and systemic manifestations of their disease, including leg length inequality and deformity, that are often more crippling than joint destruction. Surgical intervention to treat bone and soft-tissue deformity, leg length inequality, and joint destruction is indicated when medical therapy has failed. Synovectomy, soft-tissue release, osteotomy, and epiphysiodesis are used to treat deformity and early joint destruction. Arthroplasty remains the primary therapy for joint destruction, although it is fraught with complications specific to this young patient population.

Suture versus screw fixation of displaced tibial eminence fractures: a biomechanical comparison.

PURPOSE: Classification and treatment of tibial eminence fractures are determined by the degree of fragment displacement. A variety of surgical procedures have been proposed to stabilize displaced fractures using both open and arthroscopic techniques. Two common fixation techniques involve use of cannulated screws and sutures tied over an anterior tibial bone bridge. We are unaware of any biomechanical studies that have compared the strength of various techniques of fixation. TYPE OF STUDY: Biomechanical study in a cadaveric model. METHODS: Seven matched pairs of fresh-frozen human cadaveric knees were stripped of all soft tissue except the anterior cruciate ligament (ACL). Simulated type III tibial eminence fractures were created using an osteotome. Fragments of each matched pair were randomized to fixation with either a single 4-mm cannulated cancellous screw with a washer or an arthroscopic suture technique using 3 No. 2 Fiberwire sutures (Arthrex, Naples, FL) passed through the tibial base of the ACL and tied over bone tunnels on the anterior tibial cortex. Specimens were then loaded with a constant load rate of 20 mm/min, and load-deformation curves were generated. The ultimate strength and stiffness were computed for each curve. The failure mode for each test was observed. A paired 2-tailed t test was used to determine the statistically significant difference between the two methods. RESULTS: Specimens fixed with Fiberwire had a mean ultimate strength of 319 N with a standard deviation of 125 N. Those fixed with cannulated screws had a mean ultimate strength of 125 N with a standard deviation of 74 N. This difference was statistically significant (P = .0038). There was no significant difference between the mean stiffness of Fiberwire constructs (63 N; SD, 50 N) and the mean stiffness of the cannulated screw constructs (20 N; SD, 32 N). The failure modes of the Fiberwire constructs included 1 ACL failure, 3 failures of suture cutting through the anterior tibial cortex, and 3 of suture cutting through the tibial eminence fragment. The single mode of failure for the cannulated screw constructs was screw pullout of cancellous bone. CONCLUSIONS: The initial ultimate strength of Fiberwire fixation of tibial eminence fractures in these specimens was significantly stronger than that of cannulated screw fixation. CLINICAL RELEVANCE: It appears that Fiberwire fixation of eminence fractures provides biomechanical advantages over cannulated screw fixation and may influence the type of treatment one chooses for patients with tibial eminence fractures.

Chronic exertional compartment syndrome: diagnosis and management.

During exercise, muscular expansion and swelling occur. Chronic exertional compartment syndrome represents abnormally increased compartment pressures and pain in the involved extremity secondary to a noncompliant musculofascial compartment. Most commonly, it occurs in the lower leg, but has been reported in the thigh, foot, upper extremity, and erector spinae musculature. The diagnosis is obtained through a careful history and physical exam, reproduction of symptoms with exertion, and pre- and post-exercise muscle tissue compartment pressure recordings. It has been postulated that increased compartment pressures lead to transient ischemia and pain in the involved extremity. However; this is not universally accepted. Other than complete cessation of causative activities, nonoperative management of CECS is usually unsuccessful. Surgical release of the involved compartments is recommended for patients who wish to continue to exercise.

Osteogenic protein-1 (bone morphogenic protein-7) combined with various adjuncts in the treatment of humeral diaphyseal nonunions.

A prospective study was conducted to determine the efficacy of using recombinant BMP-7 (rhOP-1) as an adjuvant in the treatment of diaphyseal humeral nonunions. Twenty-three consecutive patients with atrophic humeral diaphyseal nonunions were treated at seven separate institutions. All nonunions were fixed with either a compression plate or an intramedullary nail in conjunction with various bone grafting techniques. Recombinant OP-1 was delivered to the fracture site in a Type I collagen carrier at the time of fixation. All fractures went on to eventual union. There were no serious complications and no adverse reactions to the rhOP-I implant. Our study suggests that rhOP-1 may be a safe and effective adjuvant for the treatment of humeral diaphyseal nonunions.

Comparison of a sliding hip screw with a trochanteric lateral support plate to an intramedullary hip screw for fixation of unstable intertrochanteric hip fractures: a cadaver study.

BACKGROUND: The lateral trochanteric support plate (LSP) was developed to prevent excessive sliding of unstable intertrochanteric femur fractures fixed with a sliding hip screw (SHS). This study compared the fracture stability and screw sliding characteristics of unstable intertrochanteric femur fractures fixed with either an SHS and LSP or an Intramedullary Hip Screw (IMHS). METHODS: Six matched pairs of cadaveric human femurs with simulated, unstable intertrochanteric femur fractures were stabilized with either an IMHS or a 135-degree SHS with an attached LSP. Inferior and lateral head displacements and lag screw sliding distances were measured for applied static loads of 750 N, before and after cycling. RESULTS: Four-part unstable intertrochanteric femur fractures showed comparable screw sliding characteristics and stability whether instrumented with an SHS and LSP or an IMHS. CONCLUSION: A sliding hip screw with an attached lateral support plate provides stability and ability to resist medial displacement of the femoral shaft similar to that seen with the IMHS.

Stiffness after total knee arthroplasty.

Postoperative stiffness is a debilitating complication of total knee arthroplasty. Preoperative risk factors include limited range of motion, underlying diagnosis, and history of prior surgery. Intraoperative factors include improper flexion-extension gap balancing, oversizing or malpositioning of components, inadequate femoral or tibial resection, excessive joint line elevation, creation of an anterior tibial slope, and inadequate resection of posterior osteophytes. Postoperative factors include poor patient motivation, arthrofibrosis, infection, complex regional pain syndrome, and heterotopic ossification. The first steps in treating stiffness are mobilizing the patient and instituting physical therapy. If these interventions fail, options include manipulation, lysis of adhesions, and revision arthroplasty. Closed manipulation is most successful within the first 3 months after total knee arthroplasty. Arthroscopic or modified open lysis of adhesions can be considered after 3 months. Revision arthroplasty is preferred for stiffness from malpositioned or oversized components. Patients who initially achieve adequate range of motion (>90 degrees of flexion) but subsequently develop stiffness more than 3 months after surgery should be assessed for intrinsic as well as extrinsic causes.

Risks associated with blood transfusion after total knee arthroplasty.

A retrospective study of 1,402 patients who underwent primary total knee arthroplasty (TKA) (1,194 unilateral, 208 bilateral) was performed. The strongest predictors for allogenic transfusion after surgery were advancing age (P<.001), low preoperative hemoglobin (P<.001), and the use of low-molecular-weight heparin postoperatively (P<.01). Pre-donation of 1 unit of autologous blood before TKA decreased the allogenic transfusion rate from a baseline of 38% to 11%, whereas pre-donating 2 units lowered the rate of breakthrough transfusion of allogenic blood to 7%. A patient with a preoperative hemoglobin >150 g/L or who is younger than age 65 with a preoperative hemoglobin >130 g/L may not benefit from pre-donation, and a high rate of wastage may result.

Sixteen-year follow-up of the cemented spectron femoral stem for hip arthroplasty.

Clinical and radiographic follow-up was performed on a consecutive series of 105 patients who underwent 120 total hip arthroplasties at the authors' institution from 1983 to 1988 with a straight, cobalt-chrome femoral stem implanted using a second-generation cementing technique. The mean age at the time of surgery was 68.5 years, and the mean follow-up was 16 years. At 16 years' follow-up, the prevalence of revision for aseptic loosening of the Spectron femoral component was only 4.2%; 5 stems were revised for aseptic loosening at a mean of 10.2 years after implantation. Sixteen-year survivorship of the component was 93.9% +/- 2.7% when revision for aseptic loosening was taken as the endpoint or 90.3% +/- 4.4% when either revision for aseptic loosening or radiographic evidence of loosening was taken as the endpoint.

Severe ulnar neuropathy after subcutaneous transposition in a collegiate tennis player.

We report the case of an "overhead" athlete (a collegiate tennis player) who developed severe ulnar neuropathy after anterior subcutaneous transposition and placement of a fasciodermal sling. Treatment consisted of opening the sling, excising suture material, releasing all other areas of potential compression, and performing anterior submuscular transposition of the ulnar nerve deep to the flexor muscle group. Two years after surgery, subjective symptoms were significantly improved, though the patient continued to experience mild medial-side elbow discomfort and intermittent paresthesia along the ulnar nerve distribution. Pain relief achieved without full sensory and motor recovery is consistent with results reported elsewhere. In short, extreme care must be taken when creating a fasciodermal sling during anterior subcutaneous transposition of the ulnar nerve.

Comparison of the LISS and a retrograde-inserted supracondylar intramedullary nail for fixation of a periprosthetic distal femur fracture proximal to a total knee arthroplasty.

Simulated supracondylar fractures were created proximal to posterior cruciate ligament-retaining total knee arthroplasty components in paired human cadaver femora and stabilized with either a retrograde-inserted locked supracondylar nail or the Less Invasive Stabilization System (LISS; Synthes USA, Paoli, PA). Loads were applied to create bending and torsional moments on the simulated fracture stabilized with either no gap or a 10-mm gap. The LISS exhibited less torsional stability with anterior (P<.001) and posterior loads (P<.01). When varus loads were applied to 10-mm-gap specimens, the specimens stabilized with a retrograde nail had an 83% reduction in fracture displacement (P<.001) and 80% less medial translation of the distal fragment (P<.001). The samples stabilized with the LISS had a 93% reduction in fracture gap displacement when a valgus load was applied with a 10-mm gap (P<.001). Overall, these results suggest that the retrograde-inserted nail may provide greater stability for the management of periprosthetic supracondylar femur fractures in patients with a posterior cruciate ligament-retaining femoral total knee arthroplasty component.