PubMed Health⌕ Search

Biomedical subjects

Michael D McKee

Publications and source records attributed to Michael D McKee.

At least 19 recordsLinked to original sources
PubMed2006

Compression plating versus intramedullary nailing of humeral shaft fractures--a meta-analysis.

BACKGROUND: The choice of plates or intramedullary nails for operatively treated humeral shaft fractures remains controversial, since randomized controlled trials have lacked sufficient power. A meta-analysis of existing trials would improve inferences regarding the treatment effect. METHODS: We reviewed randomized trials in Medline, Cochrane and SciSearch, along with other sources of published randomized trials from 1969-2000. Of 215 citations identified, only 3 studies were included. RESULTS: The 3 studies (involving 155 patients) were pooled, since they were homogeneous (p > 0.1). Plate fixation gave a lower relative risk of reoperation than intramedullary nailing (RR = 0.26, 95% CI 0.007-0.9, p = 0.03). This translated to a risk reduction of 74% for reoperation when plate fixation was employed. Thus, 1 reoperation could be prevented for every 10 patients treated with plates. Plate fixation also reduced the risk of shoulder problems in comparison to intramedullary nails (RR = 0.10, 95% CI 0.03-0.4, p = 0.002). INTERPRETATION: Plate fixation of humeral shaft fractures may reduce the risk of reoperation and shoulder impingement. The cumulative evidence remains inconclusive, and a larger trial is needed in order to confirm these findings.

Bone Nails↗
PubMed2006

A randomized, controlled trial of distal radius fractures with metaphyseal displacement but without joint incongruity: closed reduction and casting versus closed reduction, spanning external fixation, and optional percutaneous K-wires.

OBJECTIVES: To compare closed reduction and casting with closed reduction and external fixation with optional K-wire fixation for distal radius fractures with metaphyseal displacement but without joint incongruity. DESIGN: Prospective study. SETTING: Multicenter study at 3 University teaching hospitals. PATIENTS/PARTICIPANTS: A total of 113 skeletally mature patients with distal radius fractures with metaphyseal displacement, but without joint incongruity, were randomized to receive 1 of 2 standardized treatment protocols. Patients were evaluated at 6 weeks, 6 months, 1 year, and 2 years. INTERVENTION: Closed reduction and casting (n = 59) or closed reduction and external fixation (n = 54). MAIN OUTCOME MEASUREMENTS: Upper extremity function was measured using upper extremity MFA domain scores, overall Jebsen Taylor scores, and pinch and grip strength tests. Global function and pain were measured using the SF-36. Radiographic evaluation and range of motion were documented. RESULTS: Upper extremity MFA scores, Jebsen Taylor scores, SF-36 bodily pain scores, and grip strength improved significantly during the first year for all patients. By 2 years, mean Jebsen Taylor scores and SF 36 bodily pain scores for patients in both groups were similar to scores for normal age- and gender-matched population controls. At all points, there was a trend for better function in the external fixation; however, this did not reach statistical significance. There was a trend for better length and palmar tilt restoration with external fixation. CONCLUSIONS: For distal radius fractures with metaphyseal displacement but with a congruous joint, there exists a trend for better functional, clinical, and radiographic outcomes when treated by immediate external fixation and optional K-wire fixation.

Adult↗
PubMed2006

Deficits following nonoperative treatment of displaced midshaft clavicular fractures.

BACKGROUND: Displaced fractures of the midpart of the clavicular shaft are generally treated nonoperatively, and few functional deficits have been reported. Whereas prior investigators have presented radiographic and surgeon-based outcomes, we used a patient-based outcome questionnaire and objective muscle-strength testing to evaluate a series of patients who had received nonoperative care for a displaced midshaft fracture of the clavicle. METHODS: We identified thirty patients (twenty-two men and eight women with a mean age of thirty-seven years) who had sustained a displaced midshaft fracture of the clavicle. All patients were treated nonoperatively. At a mean of fifty-five months, and a minimum of twelve months, outcomes were measured with the Constant shoulder score and the DASH (Disabilities of the Arm, Shoulder and Hand) patient questionnaire. In addition, objective shoulder muscle-strength testing was performed with the Baltimore Therapeutic Equipment Work Simulator, with the uninjured arm serving as a control. RESULTS: The range of motion was well maintained, with flexion averaging 170 degrees +/- 20 degrees and abduction averaging 165 degrees +/- 25 degrees . Compared with the strength of the uninjured shoulder, the strength of the injured shoulder was reduced to 81% for maximum flexion, 75% for endurance of flexion, 82% for maximum abduction, 67% for endurance of abduction, 81% for maximum external rotation, 82% for endurance of external rotation, 85% for maximum internal rotation, and 78% for endurance of internal rotation (p < 0.05 for all values). The mean Constant score was 71 points, and the mean DASH score was 24.6 points, indicating substantial residual disability. CONCLUSIONS: Traditionally, good results with minimal functional deficits have been reported following nonoperative treatment of clavicular fractures. However, surgeon-based methods of evaluation may be insensitive to loss of muscle strength. We detected residual deficits in shoulder strength and endurance in this patient population, which may be related to the significant level of dysfunction detected by the patient-based outcome measures.

Adult↗
PubMed2006

Survivorship analysis and radiographic outcome following tantalum rod insertion for osteonecrosis of the femoral head.

BACKGROUND: For early stages of osteonecrosis, preservation of the femoral head is the primary objective; however, there has not been a consensus on how best to achieve this goal. Core decompression alone is associated with a lack of structural support with inconsistent outcomes, whereas vascularized fibular grafting requires an extensive surgical procedure with high donor-site morbidity and prolonged rehabilitation. The adjunctive use of a porous tantalum implant offers the advantages of core decompression, structural support, minimally invasive surgery, and no donor-site morbidity. The purpose of this study was to assess the survivorship and to evaluate the clinical results and radiographic outcomes of hips in which osteonecrosis of the femoral head was treated with core decompression and a porous tantalum implant. METHODS: We evaluated fifty-four patients (sixty consecutive hips) in whom osteonecrosis of the femoral head was treated with core decompression and insertion of a porous tantalum implant. Fifty-two patients (fifty-eight hips) were available for follow-up at a mean of twenty-four months. All patients were sixty-five years of age or younger (mean age, thirty-five years). According to the classification system of Steinberg et al., one hip (2%) had stage-I disease, forty-nine hips (84%) had stage-II disease, and eight hips (14%) had stage-III disease. Outcome measures that were used included a limb-specific score (Harris hip score), radiographic outcome measures, and survivorship analysis with revision to total hip arthroplasty as the end point. RESULTS: Overall, nine hips (15.5%) were converted to total hip arthroplasty, including six with stage-II disease and three with stage-III disease. The overall survival rates were 91.8% (95% confidence interval, 87.8% to 95.8%) at twelve months, 81.7% (95% confidence interval, 75.8% to 87.6%) at twenty-four months, and 68.1% (95% confidence interval, 54.7% to 81.5%) at forty-eight months. The absence of chronic systemic diseases resulted in a survival rate of 92% at forty-eight months (95% confidence interval, 87.4% to 96.4%). CONCLUSIONS: Treatment of early stage osteonecrosis of the femoral head with core decompression and a porous tantalum implant can be accomplished with a minimally invasive technique and no donor-site morbidity. The early clinical results show encouraging survival rates in patients who do not have chronic systemic disease, especially in association with early stage disease. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

Adolescent↗
PubMed2006

Total hip arthroplasty following failure of free vascularized fibular graft.

BACKGROUND: Many treatments for osteonecrosis of the femoral head, including the use of a free vascularized fibular graft, have been advocated in an attempt to delay the need for hip arthroplasty. The purpose of this study was to document the clinical and radiographic results of total hip arthroplasty performed following failure of a free vascularized fibular grafting procedure. METHODS: Twenty total hip arthroplasties in eighteen patients who had previously undergone a free vascularized fibular grafting procedure for the treatment of osteonecrosis were retrospectively reviewed. A straight-stem femoral component was used in twelve hips, a tapered femoral component with removal of residual fibular graft was used in five hips, and a tapered stem without graft removal was used in three hips. The twelve hips with a straight-stem femoral component and previous vascularized fibular grafting were compared with thirty-six osteonecrotic hips in thirty other patients who had undergone total hip arthroplasty but had not had previous free vascularized fibular grafting. The radiographic outcomes with respect to initial femoral component alignment and subsequent migration and the clinical outcomes were compared. RESULTS: Analysis of the immediate postoperative radiographs demonstrated significantly improved alignment of the femoral component when a high-speed burr had been used to remove residual fibular graft (p = 0.001), although doing so did significantly increase both the intraoperative blood loss (p = 0.017) and the operative time (p = 0.0002). There was no significant difference in the amount of migration of either the acetabular or the femoral component between the control and study groups at the time of the most recent follow-up. When comparing patients with or without a previous free vascularized fibular graft, the mean postoperative scores at three years were significantly worse in patients who had undergone a previous free vascularized fibular graft (p = 0.03). One revision occurred in the study group at seventy-two months due to acetabular wear, and one revision occurred in the control group at 108 months due to aseptic loosening. CONCLUSIONS: This study raises concern that the outcome of total hip arthroplasty in patients who previously underwent a free vascularized fibular graft for the treatment of osteonecrosis of the femoral head may be worse than that in patients without previous free vascularized fibular grafting. The intraoperative use of a high-speed burr can improve the alignment of the femoral component by removing more of the residual graft. However, this technique does increase intraoperative blood loss and operative time. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

Adult↗
PubMed2006

Management of segmental bony defects: the role of osteoconductive orthobiologics.

Our knowledge about, and the availability of, orthobiologic materials has increased exponentially in the last decade. Although previously confined to the experimental or animal-model realm, several orthobiologics have been shown to be useful in a variety of clinical situations. As surgical techniques in vascular anastomosis, soft-tissue coverage, limb salvage, and fracture stabilization have improved, the size and frequency of bony defects (commensurate with the severity of the initial injury) have increased, as well. Because all methods of managing segmental bony defects have drawbacks, a need remains for a readily available, void-filling, inexpensive bone substitute. Such a bone substitute fulfills a permissive role in allowing new bone to grow into a given defect. Such potential osteoconductive materials include ceramics, calcium sulfate or calcium phosphate compounds, hydroxyapatite, deproteinized bone, corals, and recently developed polymers. Some materials that have osteoinductive properties, such as demineralized bone matrix, also display prominent osteoconductive properties.

Animals↗
PubMed2005

Treatment of osteopenic humeral shaft nonunion with compression plating, humeral cortical allograft struts, and bone grafting.

Surgical stabilization of humeral shaft nonunions can be difficult to achieve if severe osteopenia or loss of bone stock is present. We present a technique whereby a 4.5-mm standard dynamic compression plate is used in conjunction with a humeral cortical allograft strut and bone grafting to stabilize humeral shaft nonunions complicated by severe bone loss. Six patients with established nonunion of the humeral shaft underwent this technique. Union was achieved at an average of 3.4 months (range 2-6 months). Our method using onlay allograft struts can provide an effective alternative in the management of humeral shaft nonunion complicated by severe osteopenia of various etiologies.

Aged↗
PubMed2005

Treatment of acute midshaft clavicle fractures: systematic review of 2144 fractures: on behalf of the Evidence-Based Orthopaedic Trauma Working Group.

BACKGROUND: Fractures of the clavicle were reported to represent 2.6% of all fractures with an overall incidence of 64 per 100,000 per year (1987, Malmö, Sweden). Midshaft fractures account for approximately 69% to 81% of all clavicle fractures. Treatment options for acute midshaft clavicle fractures include nonoperative treatment (mostly sling or figure-of-eight bandage), open reduction and internal fixation with plates, and closed or open reduction and internal fixation with intramedullary pins, wires, or a nail. Most surgeons prefer nonoperative treatment of nondisplaced midshaft clavicle fractures. However, the optimal treatment option for isolated acute displaced midshaft clavicle fractures remains controversial. OBJECTIVES: This study was designed to systematically summarize and compare results of different treatment options (nonoperative, operative extramedullary fixation, and operative intramedullary fixation) in the management of midshaft clavicle fractures, specifically for displaced fractures.

Clavicle↗
PubMed2005

Posterolateral rotatory instability of the elbow following radial head resection.

BACKGROUND: Resection is a common procedure for the treatment of comminuted fractures of the radial head. While radial head resection is associated with a high success rate when performed for appropriate indications, a number of well-defined biomechanical complications have been reported following this procedure, including proximal migration of the radius, the development of valgus deformity, and recurrent elbow instability in the acute setting. However, posterolateral rotatory instability has not previously been recognized as a complication of radial head resection. While the absence of the radial head makes the diagnosis difficult, we have identified a series of patients with posterolateral rotatory instability following radial head resection. We believe that this instability is secondary to unrecognized lateral ulnar collateral ligament deficiency. METHODS: Between November 1995 and September 2000, forty-two patients were evaluated because of elbow or forearm complaints following radial head resection. Seven patients (17%) were diagnosed with posterolateral rotatory instability on the basis of characteristic clinical and radiographic findings. RESULTS: The study group included five men and two women with a mean age of forty-two years. All seven patients had had radial head excision for the treatment of a comminuted radial head fracture at a mean of forty-four months (range, four months to sixteen years) prior to referral. All seven patients had lateral elbow pain, a sense of instability and/or weakness, and a positive lateral pivot-shift test. Posterolateral rotatory instability secondary to lateral ulnar collateral ligament insufficiency was confirmed intraoperatively in the four patients who were managed surgically. CONCLUSIONS: Clinicians should be aware that posterolateral rotatory instability may be a cause of unexplained elbow pain and instability following radial head resection. This diagnosis has implications for the prevention and treatment of this condition.

Adult↗
PubMed2005

Standard surgical protocol to treat elbow dislocations with radial head and coronoid fractures. Surgical technique.

BACKGROUND: The results of elbow dislocations with associated radial head and coronoid fractures are often poor because of recurrent instability and stiffness from prolonged immobilization. We managed these injuries with a standard surgical protocol, postulating that early intervention, stable fixation, and repair would provide sufficient stability to allow motion at seven to ten days postoperatively and enhance functional outcome. METHODS: We retrospectively reviewed the results of this treatment performed, at two university-affiliated teaching hospitals, in thirty-six consecutive patients (thirty-six elbows) with an elbow dislocation and an associated fracture of both the radial head and the coronoid process. Our surgical protocol included fixation or replacement of the radial head, fixation of the coronoid fracture if possible, repair of associated capsular and lateral ligamentous injuries, and in selected cases repair of the medial collateral ligament and/or adjuvant-hinged external fixation. Patients were evaluated both radiographically and with a clinical examination at the time of the latest follow-up. RESULTS: At a mean of thirty-four months postoperatively, the flexion-extension arc of the elbow averaged 112 degrees +/- 11 degrees and forearm rotation averaged 136 degrees +/- 16 degrees . The mean Mayo Elbow Performance Score was 88 points (range, 45 to 100 points), which corresponded to fifteen excellent results, thirteen good results, seven fair results, and one poor result. Concentric stability was restored to thirty-four elbows. Eight patients had complications requiring a reoperation: two had a synostosis; one, recurrent instability; four, hardware removal and elbow release; and one, a wound infection. CONCLUSIONS: Use of our surgical protocol for elbow dislocations with associated radial head and coronoid fractures restored sufficient elbow stability to allow early motion postoperatively, enhancing the functional outcome. We recommend early operative repair with a standard protocol for these injuries.

Collateral Ligaments↗
PubMed2004

Fracture-dislocation of the elbow: diagnosis, treatment, and prognosis.

There are two main goals for the surgeon treating injuries around the elbow joint: the maintenance of a stable, concentric reduction of the joint and the initiation of early motion to help prevent stiffness and maximize functional out-come. The presence of a fracture decreases joint stability and increases the risk for early subluxation or dislocation with motion. Operative repair thus is indicated for most of these injuries to restore sufficient osseoligamentous support to allow safe, early motion and provide a stable functional elbow in the long term.

Elbow Joint↗
PubMed2004

Four part fractures of the proximal humerus.

BACKGROUND: Four part fractures of the proximal humerus represent approximately 5% of all proximal humeral fractures. Treatment options for these displaced fractures include nonoperative treatment, open reduction and internal fixation, and arthroplasty. Presently, there is a lack of consensus on the optimal management strategy for this complex injury. OBJECTIVE: To determine the effect of alternate devices in the management of four part proximal humerus fractures in patients on the risks of reoperation, need for implant removal at 1 year, and pain.

Arthroplasty↗
PubMed2004

Midshaft malunions of the clavicle. Surgical technique.

BACKGROUND: The purpose of this study was to analyze the functional results of corrective osteotomy of a malunited clavicular fracture in patients with chronic pain, weakness, neurologic symptoms, and dissatisfaction with the appearance of the shoulder. METHODS: We identified fifteen patients (nine men and six women with a mean age of thirty-seven years) who had a malunion following nonoperative treatment of a displaced midshaft fracture of the clavicle. The mean time from the injury to presentation was three years (range, one to fifteen years). Outcome scores revealed major residual deficits. The mean amount of clavicular shortening was 2.9 cm (range, 1.6 to 4.0 cm). All patients underwent corrective osteotomy of the malunion through the original fracture line and internal fixation. RESULTS: At the time of follow-up, at a mean of twenty months (range, twelve to forty-two months) post-operatively, the osteotomy site had united in fourteen of the fifteen patients. All fourteen patients expressed satisfaction with the result. The mean DASH (Disabilities of the Arm, Shoulder and Hand) score for all fifteen patients improved from 32 points preoperatively to 12 points at the time of follow-up (p = 0.001). The mean shortening of the clavicle improved from 2.9 to 0.4 cm (p = 0.01). There was one nonunion, and two patients had elective removal of the plate. CONCLUSIONS: Malunion following clavicular fracture may be associated with orthopaedic, neurologic, and cosmetic complications. In selected cases, corrective osteotomy results in a high degree of patient satisfaction and improves patient-based upper-extremity scores.

Adult↗
PubMed2004

Standard surgical protocol to treat elbow dislocations with radial head and coronoid fractures.

BACKGROUND: The results of elbow dislocations with associated radial head and coronoid fractures are often poor because of recurrent instability and stiffness from prolonged immobilization. We managed these injuries with a standard surgical protocol, postulating that early intervention, stable fixation, and repair would provide sufficient stability to allow motion at seven to ten days postoperatively and enhance functional outcome. METHODS: We retrospectively reviewed the results of this treatment performed, at two university-affiliated teaching hospitals, in thirty-six consecutive patients (thirty-six elbows) with an elbow dislocation and an associated fracture of both the radial head and the coronoid process. Our surgical protocol included fixation or replacement of the radial head, fixation of the coronoid fracture if possible, repair of associated capsular and lateral ligamentous injuries, and in selected cases repair of the medial collateral ligament and/or adjuvant hinged external fixation. Patients were evaluated both radiographically and with a clinical examination at the time of the latest follow-up. RESULTS: At a mean of thirty-four months postoperatively, the flexion-extension arc of the elbow averaged 112 degrees +/- 11 degrees and forearm rotation averaged 136 degrees +/- 16 degrees. The mean Mayo Elbow Performance Score was 88 points (range, 45 to 100 points), which corresponded to fifteen excellent results, thirteen good results, seven fair results, and one poor result. Concentric stability was restored to thirty-four elbows. Eight patients had complications requiring a reoperation: two had a synostosis; one, recurrent instability; four, hardware removal and elbow release; and one, a wound infection. CONCLUSIONS: Use of our surgical protocol for elbow dislocations with associated radial head and coronoid fractures restored sufficient elbow stability to allow early motion postoperatively, enhancing the functional outcome. We recommend early operative repair with a standard protocol for these injuries.

Adult↗
PubMed2004

Effect of distal humeral varus deformity on strain in the lateral ulnar collateral ligament and ulnohumeral joint stability.

BACKGROUND: Recent reports have implicated cubitus varus deformity as a risk factor for the development of late posterolateral rotatory instability of the elbow. The purpose of this study was to determine the biomechanical relationship between cubitus varus and strain in the lateral ulnar collateral ligament and subluxation of the ulnohumeral joint as it relates to posterolateral rotatory instability. METHODS: Eleven fresh-frozen cadaveric elbow joints were mounted in an apparatus that allowed active elbow motion. Supracondylar osteotomies were performed to create cubitus varus deformities of 0 degrees to 30 degrees in 5 degrees increments. Each elbow was loaded with a supination moment of 1.2 Nm and a resistive triceps extension force. Strain in the lateral ulnar collateral ligament and widening of the ulnohumeral joint were measured at each position of varus, and the resulting strain and joint-widening values were averaged. RESULTS: Strain in the lateral ulnar collateral ligament was found to increase as the cubitus varus deformity increased. Likewise, the ulnohumeral joint space was seen to progressively widen with increasing cubitus varus. Strain was significantly increased at 30 degrees of varus deformity (p = 0.03), and widening of the ulnohumeral joint space was significantly increased at 25 degrees of varus deformity (p = 0.004). When differences in the size of the cadaveric specimens were accounted for in an analysis of covariance, ligament strain was significantly increased at 25 degrees of varus (p = 0.005) and widening of the ulnohumeral joint space, at 20 degrees (p = 0.01). CONCLUSIONS: Cubitus varus deformity of the elbow increases strain in the lateral ulnar collateral ligament, with a corresponding increase in ulnohumeral joint-opening consistent with the posterolateral rotatory instability of the elbow seen clinically.

Aged↗
PubMed2003

Sliding osteotomy for deformity correction following malunion of volarly displaced distal radial fractures.

OBJECTIVE: To determine the outcome after a sliding osteotomy for deformity correction following malunion of volarly displaced distal radius fractures. DESIGN: Retrospective review of a consecutive patient series. SETTING: A university-affiliated, tertiary-care center. PATIENTS/INTERVENTION: Ten patients with symptomatic distal radius malunion following a volarly displaced distal radial fracture (Smith's fracture) were treated with an oblique sliding osteotomy and plate fixation, through a volar approach, without using an iliac crest bone graft. Five men and five women with an average age of 41.9 years were followed for an average of 2.7 years postoperatively. MAIN OUTCOME MEASUREMENTS: Range of motion, grip strength, Fernandez wrist score, radiographic parameters. RESULTS: At latest follow-up, wrist extension improved from an average of 37 degrees preoperatively to 70 degrees postoperatively (P = 0.002), wrist flexion improved from an average of 40 degrees to 65 degrees (P = 0.012), and supination improved from an average of 31 degrees to 68 degrees (P = 0.002). Postoperative radiographs revealed an average deformity correction of 10.6 degrees of volar tilt, 7.7 degrees of radial inclination, 5.8 mm of ulnar variance, and 10.4 mm of volar translation. Using the Fernandez point score (0-20) system, the average overall score improved from 10.5 preoperatively to 17.6 postoperatively (P = 0.0001). Functional outcome was rated as excellent or good in 9 of 10 patients and fair in 1 patient (who experienced residual problems due to persistent ulnar-sided pain). There were two reoperations (one hardware removal, one distal ulnar hemiresection). CONCLUSIONS: This method reliably restores distal radial anatomy, decreases pain, and improves supination without requiring iliac crest bone grafting.

Adult↗
PubMed2003

Methodologic issues in randomized controlled trials of surgical interventions.

A physician's ability to make conclusions about the relative efficacy of interventions based on their clinical experience is limited frequently. Therefore, surgeons commonly use research evidence to guide their clinical practice. The randomized controlled trial is the strongest study design. However, randomization in itself does not guarantee the trial results are valid (free from bias). Understanding the potential impact of various methodologic features of a randomized controlled trial allows a clinician to determine the validity of a trial. We present a guide for evaluating the validity of randomized controlled trials giving special consideration to issues confronted in surgical trials.

Humans↗