Functional outcomes of distal humeral fractures managed nonoperatively in medically unwell and lower-demand elderly patients.

BACKGROUND: There is scant contemporary literature describing the outcomes of nonoperative management of distal humeral fractures. The aim of this study was to report the functional and radiographic outcomes after nonoperative management of distal humeral fractures. METHODS: Between 2007 and 2013, 32 low-demand, medically unwell, or older patients with distal humeral fractures were treated nonoperatively. At the time of this study, 8 patients had died of unrelated causes, and 5 patients were lost to follow-up. The remaining 19 patients, with a mean age of 77 years, were available for a comprehensive assessment. RESULTS: At a mean of 27 ± 14 months of follow-up, 68% (13 of 19) of patients reported good to excellent subjective outcomes. Outcomes in 2 patients were classified as poor, one of whom underwent total elbow arthroplasty as a result. Overall, the mean score on the Patient Rated Elbow Evaluation was 16 ± 23 and the Mayo Elbow Performance Index was 90 ± 11. When the injured was compared with the uninjured side, extension (22° ± 11° vs 8° ± 12°; P = .025) and flexion (128° ± 16° vs 142° ± 7°; P = .002) were significantly worse in the injured elbows. The fracture union rate was 81% (22 of 27) at a mean radiographic follow-up of 12 months. CONCLUSIONS: Satisfactory outcomes were observed after the nonoperative management of selected distal humeral fractures in lower-demand, medically unwell, or older patients. Fracture union can be expected in most patients. In the uncommon instance when an unsatisfactory outcome occurs, successful salvage can be achieved with conversion to a total elbow arthroplasty.

Do revised hip resurfacing arthroplasties lead to outcomes comparable to those of primary and revised total hip arthroplasties?

BACKGROUND: A theoretical clinical advantage of hip resurfacing (HR) is the preservation of femoral bone. HR femoral component revision reportedly yields postoperative function comparable to that of primary THA. However, few studies have looked at the outcome of both HR femoral and acetabular side revisions. QUESTIONS/PURPOSES: We determined whether (1) patients undergoing HR revision to THA have perioperative measures and outcome scores comparable to those of patients undergoing primary THA or revision of primary THA and (2) patients undergoing HR revision of both components have perioperative measures and outcome scores comparable to those of patients undergoing HR revision of the femoral component only. METHODS: We retrospectively reviewed and compared 22 patients undergoing revision HR to a THA to a matched (age, sex, BMI) group of 23 patients undergoing primary THA and 12 patients undergoing primary THA revision. Patients completed the WOMAC and SF-12 questionnaires before surgery and at latest followup (range, 24-84 months for HR revision, 28-48 months for primary THA, and 24-48 months for revision THA). Blood loss, days in hospital, complications, and outcome scores were compared among groups. RESULTS: We observed no differences in SF-12 scores but observed lower WOMAC stiffness, function, and total scores in the HR revision group than in the primary THA group. Patients undergoing HR revision of both components had comparable SF-12 and WOMAC stiffness, function, and total scores but overall lower WOMAC pain scores compared to patients undergoing HR revision of the femoral side only. The HR revision group had greater intraoperative blood loss compared to the primary THA group but not the revision THA group. CONCLUSIONS: The perioperative measures and outcome scores of HR revision are comparable to those of revision THA but not primary THA. Longer followup is required to determine whether these differences persist. Patients undergoing HR revision of one or both components can expect comparable stiffness and function. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Fixation of Anteromedial Coronoid Facet Fractures: A Biomechanical Evaluation of Plated Versus Screw Constructs.

OBJECTIVE: To examine the stability of plate (locking and non-) versus screw constructs in the fixation of these fractures. METHODS: An anteromedial coronoid facet fracture (OTA/AO type 21-B1, O'Driscoll type 2, subtype 3) was simulated in 24 synthetic ulna bones that were then assigned to 3 fracture fixation groups: non-locking plate, locking plate (LP), or screw fixation. Each construct was first cycled in tension (through a simulated medial collateral ligament) and then in compression. They were then loaded to failure (displacement >2 mm). Fracture fragment displacement was recorded with an optical tracking system. RESULTS: During tension testing, a mean maximum fragment displacement of 12 ± 13 and 14 ± 9 µm was seen in the locking and non-locking constructs, respectively. There was no difference in fragment motion between the plated constructs. All screw-only fixed constructs failed during the tension protocol. During compression testing, the mean maximum fragment displacement for the screw-only construct (64 ± 79 µm) was significantly greater than locking (9 ± 5 µm) and non-locking constructs (10 ± 9 µm). During load to failure testing, the maximum load to failure in the screw-only group (316 ± 83 N) was significantly lower than locking (650.4 ± 107 N) and non-locking constructs (550 ± 76 N). There was no difference in load to failure between the plated groups. CONCLUSION: Fixation of anteromedial coronoid fractures (type 2, subtype 3) is best achieved with a plating technique. Although LPs had greater stiffness, they did not offer any advantage over conventional non-LPs with respect to fracture fragment displacement in this study. CLINICAL RELEVANCE: Isolated screw fixation showed inferior stability when compared with plate constructs for these fractures. This could result in loss of fracture reduction leading to instability and posttraumatic arthrosis.

Lateral Elbow Exposures: The Extensor Digitorum Communis Split Compared with the Kocher Approach.

INTRODUCTION: In comparison with the frequently used modified Kocher approach, the extensor digitorum communis (EDC) splitting approach allows improved access to the anterior half of the radial head, which is most commonly fractured, while reducing the risk of iatrogenic injury to the lateral collateral ligament. STEP 1 MAKE THE INCISION MODIFIED KOCHER APPROACH: Make an oblique 7-cm lateral incision beginning at the proximal edge of the lateral epicondyle and extending distally over the center of the radial head toward the posterior ulnar border of the extensor carpi ulnaris muscle belly. STEP 2 DEVELOP THE INTERVAL BETWEEN THE ANCONEUS AND THE EXTENSOR CARPI ULNARIS: Identify and develop the intermuscular interval between the anconeus and the extensor carpi ulnaris. STEP 3 PERFORM THE LATERAL ELBOW CAPSULOTOMY: Longitudinally incise the lateral elbow capsule and annular ligament anterior to the lateral ulnar collateral ligament. STEP 4 THE EXTENDED MODIFIED KOCHER APPROACH: Extend the exposure by elevating the common extensor origin (extensor carpi radialis brevis, EDC, and extensor carpi ulnaris) proximally off the lateral epicondyle and reflect it anteriorly. STEP 5 MAKE THE INCISION EDC SPLITTING APPROACH: Make a longitudinal oblique 5 to 6-cm lateral incision beginning at the proximal edge of the lateral epicondyle and extending distally over the radial head toward the Lister tubercle. STEP 6 IDENTIFY AND SPLIT THE EDC: The EDC tendon is identified and bisected longitudinally starting proximally at its origin on the lateral epicondyle and extending 20 mm distally from the radiocapitellar joint. STEP 7 PERFORM THE LATERAL ELBOW CAPSULOTOMY: The annular ligament and joint capsule are then incised collinear with the EDC split anterior to the equator of the capitellum. STEP 8 EXTENDED EDC SPLITTING APPROACH: Extend the exposure by detaching the anterior half of the EDC tendon and the extensor carpi radialis brevis tendon from the lateral epicondyle. STEP 9 LAYERED CLOSURE: Perform an interrupted layered closure. RESULTS: In our recent cadaveric study, we quantitatively compared the modified Kocher and EDC splitting approaches in order to determine which provided the greatest exposure of the anterior aspect of the radial head, which is most commonly fractured.IndicationsContraindicationsPitfalls & Challenges.

Crista Supinatoris Fractures of the Proximal Part of the Ulna: Surgical Technique.

INTRODUCTION: Open reduction and internal fixation of crista supinatoris fractures is required when the elbow is unstable despite appropriate nonoperative management and when a patient is undergoing surgical treatment of a periarticular elbow fracture-dislocation. STEP 1 SKIN INCISION AND SURGICAL APPROACH: Use a posterior or lateral skin incision according to your preference and then utilize the Kocher interval to access the joint, lateral collateral ligament, and crista supinatoris or, in the setting of a proximal ulnar fracture, use the Boyd interval. STEP 2 MANAGEMENT OF ASSOCIATED INJURIES: Crista supinatoris fractures have not been identified in isolation; address associated injuries such as radial head/neck fractures, capitellar fractures, and coronoid fractures first. STEP 3 EVALUATION OF ELBOW STABILITY: If elbow instability persists after the concomitant injuries have been addressed, fix the crista supinatoris. STEP 4 EXPOSURE OF THE CRISTA SUPINATORIS: Expose the fracture fragment and base of the crista supinatoris. STEP 5 REDUCTION AND FIXATION OF THE CRISTA SUPINATORIS FRACTURE: Obtain an anatomic reduction and fixation of the crista supinatoris fracture to appropriately tension the lateral ulnar collateral ligament. STEP 6 REEVALUATION OF ELBOW STABILITY: Gently evaluate the stability of the elbow following repair of the crista supinatoris fracture. STEP 7 POSTOPERATIVE CARE: Initiate rehabilitation on the basis of intraoperative stability and concomitant injuries. RESULTS: We recently conducted a retrospective review of the outcomes of twelve patients with a fracture of the crista supinatoris.IndicationsContraindicationsPitfalls & Challenges.

Objective analysis of lateral elbow exposure with the extensor digitorum communis split compared with the Kocher interval.

BACKGROUND: The most widely used surgical approach to treat radial head fractures is through the Kocher interval. However, the extensor digitorum communis (EDC) splitting approach is thought to allow easier access to the anterior half of the radial head, which is more commonly fractured. The aim of this cadaveric study was to compare the osseous and articular surface areas visible through the EDC split and the Kocher interval. METHODS: Four approaches were used in fresh frozen cadaveric upper extremities: EDC splitting (n = 6), modified Kocher (n = 6), extended EDC splitting (n = 6), and extended modified Kocher (n = 4). For each approach, the osseous and articular surface areas visualized were outlined with use of a burr. Each elbow was then stripped of soft tissue and a digitized three-dimensional model was created with use of a surface scanning system. The visible surface area obtained with each approach was mapped and quantified with use of the markings created with the burr. RESULTS: The EDC splitting approach provided greater exposure of the anterior half of the radial head (median, 100%) compared with the modified Kocher approach (68%, p < 0.05). The extended modified Kocher and extended EDC splitting approaches provided comparable visualization of the distal aspect of the humerus, capitellum, radial head, and coronoid process. CONCLUSIONS: The results suggest that the EDC splitting approach provides more reliable visualization of the anterior half of the radial head while minimizing soft-tissue dissection and reducing the risk of iatrogenic injury to the lateral ulnar collateral ligament.

Zn2+-catalyzed methanolysis of phosphate triesters: a process for catalytic degradation of the organophosphorus pesticides paraoxon and fenitrothion.

The methanolyses of two neutral phosphorus triesters, paraoxon (1) and fenitrothion (3), were investigated as a function of added Zn(OTf)(2) or Zn(ClO(4))(2) in methanol at 25 degrees C either alone or in the presence of equimolar concentrations of the ligands phenanthroline (4), 2,9-dimethylphenanthroline (5), and 1,5,9-triazacyclododecane (6). The catalysis requires the presence of methoxide, and when studied as a function of added NaOCH(3), the rate constants (k(obs)) for methanolysis of Zn(2+) alone or in the presence of equimolar 4 or 5 maximize at different [(-)OCH(3)]/[Zn(2+)](total) ratios of 0.3, 0.5, and 1.0, respectively. Plots of k(obs) vs [Zn(2+)](total) either alone or in the presence of equimolar ligands 4 and 5 at the [(-)OCH(3)]/[Zn(2+)](total) ratios corresponding to the rate maxima are curved and show a nonlinear dependence on [Zn(2+)](total). In the cases of 4 and 5, this is explained as resulting from formation of a nonactive dimer, formulated as a bis-mu-methoxide-bridged form (L:Zn(2+)((-)OCH(3))(2)Zn(2+):L) in equilibrium with an active monomeric form (L:Zn(2+)((-)OCH(3))). In the case of the Zn(2+):6 system, no dimeric forms are present as can be judged by the strict linearity of the plots of k(obs) vs [Zn(2+)](total) in the presence of equimolar 6 and (-)OCH(3). Analysis of the potentiometric titration curves for Zn(2+) alone and in the presence of the ligands allows calculation of the speciation of the various Zn(2+) forms and shows that the binding to ligands 4 and 6 is very strong, while the binding to ligand 5 is weaker. Overall the best catalytic system is provided by equimolar Zn(2+), 5, and (-)OCH(3), which exhibits excellent turnover of the methanolysis of paraoxon when the substrate is in excess. At a concentration of 2 mM in each of these components, which sets the pH of the solution at 9.5, the acceleration of the methanolysis of paraoxon and fenitrothion relative to the methoxide reaction is 1.8 x 10(6)-fold and 13 x 10(6)-fold, respectively. A mechanism for the catalyzed reactions is proposed which involves a dual role for the metal ion as a Lewis acid and source of nucleophilic Zn(2+)-bound (-)OCH(3).