Robert W. Bucholz

Recombinant human BMP-2 and allograft compared with autogenous bone graft for reconstruction of diaphyseal tibial fractures with cortical defects : A randomized, controlled trial

BACKGROUND Currently, the treatment of diaphyseal tibial fractures associated with substantial bone loss often involves autogenous bone-grafting as part of a staged reconstruction. Although this technique results in high healing rates, the donor-site morbidity and potentially limited supply of suitable autogenous bone in some patients are commonly recognized drawbacks. The purpose of the present study was to investigate the benefit and safety of the osteoinductive protein recombinant human bone morphogenetic protein-2 (rhBMP-2) when implanted on an absorbable collagen sponge in combination with freeze-dried cancellous allograft. METHODS Adult patients with a tibial diaphyseal fracture and a residual cortical defect were randomly assigned to receive either autogenous bone graft or allograft (cancellous bone chips) for staged reconstruction of the tibial defect. Patients in the allograft group also received an onlay application of rhBMP-2 on an absorbable collagen sponge. The clinical evaluation of fracture-healing included an assessment of pain with full weight-bearing and fracture-site tenderness. The Short Musculoskeletal Function Assessment (SMFA) was administered before and after treatment. Radiographs were used to document union, the presence of extracortical bridging callus, and incorporation of the bone-graft material. RESULTS Fifteen patients were enrolled in each group. The mean length of the defect was 4 cm (range, 1 to 7 cm). Ten patients in the autograft group and thirteen patients in the rhBMP-2/allograft group had healing without further intervention. The mean estimated blood loss was significantly less in the rhBMP-2/allograft group. Improvement in the SMFA scores was comparable between the groups. No patient in the rhBMP-2/allograft group had development of antibodies to BMP-2; one patient had development of transient antibodies to bovine type-I collagen. CONCLUSIONS The present study suggests that rhBMP-2/allograft is safe and as effective as traditional autogenous bone-grafting for the treatment of tibial fractures associated with extensive traumatic diaphyseal bone loss. LEVEL OF EVIDENCE Therapeutic Level II. See Instructions to Authors for a complete description of levels of evidence.

Fixation with bioabsorbable screws for the treatment of fractures of the ankle

One hundred and fifty-five patients who had a closed, displaced medial malleolar, bimalleolar, or trimalleolar fracture of the ankle were managed with medial malleolar fixation with use of either 4.0-millimeter orientruded polylactide screws (eighty-three patients, study group) or 4.0-millimeter stainless-steel screws (seventy-two patients, control group). All lateral malleolar fractures were stabilized with standard metallic implants. At an average of thirty-seven months (range, twenty-one to fifty-nine months), the radiographic and functional results in the two groups were equivalent. Differences between the two groups with regard to the rates of operative and postoperative complications were not statistically significant. Late spontaneous drainage of the hydrolyzed polylactide was not noted in any patient in the study group. The prevalence of late tenderness over the medial malleolar implant was lower in the patients in whom the fracture had been stabilized with polylactide screws. We conclude that polylactide screws are a safe and effective alternative to stainless-steel screws for the fixation of displaced medial malleolar fractures.

Effect of Recombinant Human Bone Morphogenetic Protein‐2 on Fracture Healing in a Goat Tibial Fracture Model

Bone morphogenetic proteins (BMPs) are considered to have important regulatory roles in skeletal embryogenesis and bone healing. Recombinant human BMPs (rhBMPs) have been shown to heal critical size defects and promote spinal fusion. We studied the effects of rhBMP‐2 in an absorbable collagen sponge (ACS) on bone healing in a large animal tibial fracture model. Bilateral closed tibial fractures were created in 16 skeletally mature goats and reduced and stabilized using external fixation. In each animal, one tibia received the study device (0.86 mg of rhBMP‐2/ACS or buffer/ACS), and the contralateral fracture served as control. The device was implanted as a folded onlay or wrapped circumferentially around the fracture. Six weeks following fracture, the animals were sacrificed and the tibiae harvested for torsional testing and histomorphologic evaluation. Radiographs indicated increased callus at 3 weeks in the rhBMP‐2/ACS treated tibiae. At 6 weeks, the rhBMP‐2/ACS wrapped fractures had superior radiographic healing scores compared with buffer groups and controls. The rhBMP‐2/ACS produced a significant increase in torsional toughness (p = 0.02), and trends of increased torsional strength and stiffness (p = 0.09) compared with fracture controls. The device placed in a wrapped fashion around the fracture produced significantly tougher callus (p = 0.02) compared with the onlay application. Total callus new bone volume was significantly increased (p = 0.02) in the rhBMP‐2/ACS fractures compared with buffer groups and controls regardless of the method of device application. The rhBMP‐2/ACS did not alter the timing of onset of periosteal/endosteal callus formation compared with controls. Neither the mineral apposition rates nor bone formation rates were affected by rhBMP‐2/ACS treatment. The increased callus volume associated with rhBMP‐2 treatment produced only moderate increases in strength and stiffness.

Treatment of Syndesmotic Disruptions of the Ankle with Bioabsorbable Screw Fixation

Background: Bioabsorbable implants have restricted indications because of their unique biochemical properties and their inferior biomechanical properties compared with those of conventional metallic implants. The purpose of this prospective study was to assess the efficacy of screws made of polylevolactic acid (PLLA) in the treatment of syndesmotic disruptions associated with ankle fractures and fracture-dislocations. Methods: Thirty-three consecutive patients with a syndesmotic disruption were managed with standard metallic plate-and-screw fixation of the malleolar fracture and with 4.5-mm polylevolactic acid screws, with purchase in four cortices, for fixation of the syndesmosis. Intraoperative radiographs confirmed reduction of the syndesmosis, and all of the patients were managed with a non-weight-bearing plaster splint or brace for six weeks. Clinical and radiographic assessment and functional evaluation with use of the Olerud-Molander scoring system were performed at the time of follow-up. Results: Ten patients were lost to follow-up prior to the twenty-four-month evaluation, leaving twenty-three patients with an average duration of follow-up of thirty-four months (range, twenty-four to forty-three months). All of the malleolar fractures healed in an anatomical position at an average of three months, and no postoperative displacement of the syndesmosis or widening of the medial clear space was detectable on radiographs. No episodes of osteolysis or late inflammation secondary to the hydrolyzed polylactide occurred. Nineteen patients (83%) had an excellent result, and four patients (17%) had a good result. All twenty-three patients returned to their preinjury level of work and activities of daily living. No patient had malunion, nonunion, loss of reduction, or complications attributable to the biomechanical or biochemical properties of the implants. Conclusions: Polylevolactic acid screws are effective in stabilizing disruption of the syndesmosis during healing of unstable ankle fractures. In this small series, the bioabsorbable screw was well tolerated, and there was no need for a second operation to remove it.

Polyglycolide Bioabsorbable Screws in the Treatment of Ankle Fractures

Twenty-one patients with unstable medial malleolar, bimalleolar, or trimalleolar ankle fractures underwent open reduction and internal fixation of the medial malleolus with 4.5-mm polyglycolide screws. All lateral malleolar fractures were internally fixed with standard metallic implants. Radiographic and clinical follow-up results were available on 16 of 21 patients. All fractures healed at an average of 3.4 months (range, 3–6 months), and there were no medial wound infections. Eight of 16 patients developed an inflammatory reaction to the biodegradable polyester at 3 to 4 months after implantation, including one who developed a sterile draining sinus tract. No surgical or nonsurgical treatment was required in those eight patients. We conclude that whereas polyester screws yield union rates and functional results similar to those of metallic screws in the treatment of medial malleolar fractures, the use of polyglycolide screws is associated with an unacceptable rate of inflammatory reactions.

Variation in hospital-level risk-standardized complication rates following elective primary total hip and knee arthroplasty

BACKGROUND Little is known about the variation in complication rates among U.S. hospitals that perform elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) procedures. The purpose of this study was to use National Quality Forum (NQF)-endorsed hospital-level risk-standardized complication rates to describe variations in, and disparities related to, hospital quality for elective primary THA and TKA procedures performed in U.S. hospitals. METHODS We conducted a cross-sectional analysis of national Medicare Fee-for-Service data. The study cohort included 878,098 Medicare fee-for-service beneficiaries, sixty-five years or older, who underwent elective THA or TKA from 2008 to 2010 at 3479 hospitals. Both medical and surgical complications were included in the composite measure. Hospital-specific complication rates were calculated from Medicare claims with use of hierarchical logistic regression to account for patient clustering and were risk-adjusted for age, sex, and patient comorbidities. We determined whether hospitals with higher proportions of Medicaid patients and black patients had higher risk-standardized complication rates. RESULTS The crude rate of measured complications was 3.6%. The most common complications were pneumonia (0.86%), pulmonary embolism (0.75%), and periprosthetic joint infection or wound infection (0.67%). The median risk-standardized complication rate was 3.6% (range, 1.8% to 9.0%). Among hospitals with at least twenty-five THA and TKA patients in the study cohort, 103 (3.6%) were better and seventy-five (2.6%) were worse than expected. Hospitals with the highest proportion of Medicaid patients had slightly higher but similar risk-standardized complication rates (median, 3.6%; range, 2.0% to 7.1%) compared with hospitals in the lowest decile (3.4%; 1.7% to 6.2%). Findings were similar for the analysis involving the proportion of black patients. CONCLUSIONS There was more than a fourfold difference in risk-standardized complication rates across U.S. hospitals in which elective THA and TKA are performed. Although hospitals with higher proportions of Medicaid and black patients had rates similar to those of hospitals with lower proportions, there is a continued need to monitor for disparities in outcomes. These findings suggest there are opportunities for quality improvement among hospitals in which elective THA and TKA procedures are performed.

Effect of psychopathology on patient-perceived outcomes of total knee arthroplasty within an indigent population.

BACKGROUND Factors other than surgical technique and implants impact patient outcomes following a total knee arthroplasty. The purpose of this study was to analyze the effects of psychopathology on the rate of improvement following total knee arthroplasty in an indigent population. METHODS One hundred and fifty-four consecutive indigent patients undergoing a primary total knee arthroplasty for arthritis were enrolled and available for follow-up. Patients were classified as having psychopathology on the basis of the presence of somatization, depression, and/or a panic or anxiety disorder as assessed with the Patient Health Questionnaire. Outcome measures were completed preoperatively and one year postoperatively. Univariate analyses, controlled for sex and age, were used to compare the rates of improvement in patients who exhibited psychopathology with the rates in those without psychopathology. RESULTS Fifty-four patients (35%) were diagnosed with at least one Axis-I psychological disorder. The psychopathology group showed significantly lower Short Form-36 mental component summary scores both at baseline and one year postoperatively (p < 0.001 for both). The psychopathology group also reported significantly higher levels of perceived disability at baseline on the Pain Disability Questionnaire (p < 0.001) and worse scores on the Western Ontario and McMaster Universities Osteoarthritis Index (p = 0.004); however, the improvement on both of these scales did not differ significantly between the two groups (p > 0.05). The Knee Society Score differed significantly between the two groups at both baseline and the one-year follow-up evaluation (p = 0.003 and p = 0.001, respectively), but there was no significant difference in the total rate of improvement between the two comparison groups (p > 0.05). CONCLUSIONS Not only is there a high prevalence of psychopathology in the indigent population, but psychopathology may result in lower patient-perceived outcome scores at one year after a total knee arthroplasty. Even though outcome scores may be worse for patients with psychopathology, our study showed that these patients still benefit, with the same degree of improvement in function.

The role of computerized tomographic scanning in the evaluation of major pelvic fractures

Twenty-five patients with double vertical fractures of the pelvic ring had evaluations by both plain radiography and computed-tomography scanning of the pelvis. In eight of the twenty-five patients, the interpretation that was made from the plain radiographs, based on the classification of Pennal et al., changed when additional anatomical information was provided by the computed-tomography scan. We recommend that computed tomography be used for: (1) double vertical fracture-dislocations of the pelvic ring in which plain radiographs are inadequate to judge pelvic stability, (2) fractures of the pelvic ring with extension into the acetabulum, and (3) major injuries to the hemipelvis that are to be treated by open reduction and internal fixation. However, due to the increased cost and radiation exposure, routine computed-tomography scanning is not justified for all injuries to the pelvic ring.

Exstrophy of the Bladder: Primary Closure after Iliac Osteotomies without External or Internal Fixation

A total of 6 consecutive infants with exstrophy of the bladder underwent iliac osteotomy in association with primary closure of the bladder without internal or external fixation of the bony pelvis. Hospitalization time was short and there were no resulting problems with healing, bony deformities or subsequent ambulation. Fixation of the bony pelvis after iliac osteotomy does not appear to be necessary in nonambulatory patients undergoing primary closure for bladder exstrophy.

Psychosocial Profiles of Indigent Patients with Severe Osteoarthritis Requiring Arthroplasty

This study documents the prevalence of Axis I diagnoses (ie, depression, anxiety, and others) and their effects on preoperative pain, disability, function, and quality of life assessments in an indigent population undergoing total joint arthroplasty. Consecutive indigent patients scheduled for total joint arthroplasty were categorized by psychosocial testing as either psychologically distressed (PD) or nonpsychologically distressed. Of the subjects, 38% were found to be psychologically distressed. The PD group had significantly lower measures on 7 of the 8 components of the Short Form-36, the Harris hip score, and Knee Society score (P < .05). The PD group also scored significantly worse on both the Western Ontario MacMaster (P < .001) and the Pain Disability Questionnaire (P < .001). There is a high prevalence of psychopathology in the indigent population undergoing total joint arthroplasty, exhibiting poorer scores on pain, disability, function, and quality of life measures before surgery.