Long-term outcomes of closed reduction and percutaneous pinning for the treatment of distal radius fractures.

PURPOSE: The purpose of this study was to review the long-term outcomes of patients with distal radius fractures treated with closed reduction and percutaneous pinning. METHODS: We retrospectively reviewed 54 patients with 55 AO type A2, A3, C1, or C2 distal radius fractures treated with closed reduction and percutaneous pinning. The average age of the patients was 57 years. All patients returned for follow-up examination at an average of 59 months, with a minimum of 22 months. Measurements included active range of motion, grip strength, pain assessment, Disabilities of the Arm, Shoulder, and Hand scores, and final radiographic assessment. The paired t-test was used to determine significant differences. RESULTS: All fractures healed within 6 weeks. Active range of motion and grip strength of the injured wrist were statistically equal to those of the uninjured wrist for each of the parameters except wrist flexion and forearm supination. However, the difference in wrist flexion was 5 degrees and the difference in supination was 4 degrees , both of which are of little clinical importance. Eighty-five percent of patients were pain free. Radiographic parameters comparing the immediate postoperative view with the views taken at final follow-up showed no significant differences. One patient required reoperation for loss of reduction after a fall in the preoperative period, and 3 others had minor complications. CONCLUSIONS: Patients treated with closed reduction and percutaneous pinning for distal radius fractures had excellent range of motion, normal Disabilities of the Arm, Shoulder, and Hand scores, and no significant differences in the radiographic parameters between fracture fixation and fracture healing. Complications were few. Pinning is an efficacious, low-cost treatment option for 2- and 3-part distal radius fractures with excellent long-term results. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

The effects of implant composition on extensor tenosynovitis in a canine distal radius fracture model.

PURPOSE: Dorsal plating of distal radius fractures with titanium plates has resulted in clinically observed tenosynovitis and tendon rupture. The goal of this study was to investigate whether titanium-based implants result in more extensor tendon inflammation than matched stainless-steel implants in a canine fracture model. METHODS: An osteotomy was created in the distal radius of 18 beagles and fixed with 2.7-mm 4-hole plates composed of commercially pure titanium, titanium alloy (Ti-Al6-V4), or 316L stainless steel. Animals were killed at an average of 4 months. Tendon gliding was assessed by applying a force at the extensor musculotendinous junction and noting gliding. Histologic grading (mild, moderate, severe) was based on cellular hypertrophy, hyperplasia, and leukocytic infiltration. RESULTS: Tendons glided freely in 100% stainless-steel specimens, 75% of titanium alloy, and 43% of commercially pure titanium groups. A severe inflammatory reaction was identified in 60% of the titanium alloy (Ti-A16-V4) group, 57% of the pure titanium group, and 0% of the stainless-steel group. CONCLUSIONS: Dorsal plating of the canine radius with commercially pure titanium or titanium alloy implants produced a greater inflammatory peritendinous response than matched stainless-steel implants.

Unipolar or bipolar hemiarthroplasty for femoral neck fractures in the elderly?

This prospective randomized trial compared the efficacy of unipolar versus bipolar hemiarthroplasty in elderly patients (> or = 65 years) with displaced femoral neck fractures in terms of quality of life and functional outcomes. One hundred fifteen patients with a mean age of 82.1 years were enrolled in this study and randomized to either unipolar or bipolar hemiarthroplasty. Quality of life and functional outcomes were assessed using the Musculoskeletal Functional Assessment instrument and Short Form-36 health survey. Seventy-eight patients completed 1 year of followup. There were no differences between the groups in estimated blood loss, length of hospital stay, mortality rate, number of dislocations, postoperative complications, or ambulatory status at 1 year. There also were no significant differences between the two groups at either point in postoperative Short Form-36 or Musculoskeletal Functional Assessment instrument scores. Results of this prospective randomized study suggest that the bipolar endoprosthesis provides no advantage in the treatment of displaced femoral neck fractures in elderly patients regarding quality of life and functional outcomes.

myo-Inositol 1,4,5-trisphosphate and Ca(2+)/calmodulin-dependent factors mediate transduction of compression-induced signals in bovine articular chondrocytes.

Although the effects of mechanical loading on chondrocyte metabolic activities have been extensively characterized, the sequence of events through which extracellular mechanical signals are transduced into chondrocytes and ultimately modulate cell activities is not well understood. Here, studies were performed to map out the sequential intracellular signalling pathways through which compression-induced signals modulate aggrecan mRNA levels in bovine articular chondrocytes. Bovine articular cartilage explants were subjected to a compressive stress of 0.1 MPa for 1 h in the presence or absence of inhibitors or antagonists of the phosphoinositol and Ca(2+)/calmodulin signalling pathways in order to determine the roles of second messengers and effector molecules of these pathways in transducing the compression-induced signals. In the absence of the inhibitors, aggrecan mRNA levels were stimulated by compression 2-4-fold relative to levels in tare-loaded (see below) explants. Treatment of the explants with graded levels of the protein kinase C inhibitor chelerythrine or bisindolylmaleimide I, followed by 1 h compressive loading, did not significantly alter the load-induced elevation of aggrecan mRNA levels. In contrast, thapsigargin, which depletes the Ins(1,4,5)P3-sensitive intracellular Ca(2+) stores, completely blocked the load response without significantly altering aggrecan mRNA levels in tare-loaded explants. Similarly, antagonists of the Ca(2+)/calmodulin signalling pathway dose-dependently or completely blocked the load-response. The results obtained demonstrate that transduction of the compression-induced aggrecan mRNA-regulating signals requires Ins(1,4,5)P3- and Ca(2+)/calmodulin-dependent signalling processes in bovine articular chondrocytes.