David Backstein

Fresh Osteochondral Allografts for Posttraumatic Knee Defects: Long-term Followup

Fresh osteochondral allograft transplantation has been an effective treatment option with promising long-term clinical outcomes for focal posttraumatic defects in the knee for young, active individuals. We examined histologic features of 35 fresh osteochondral allograft specimens retrieved at the time of subsequent graft revision, osteotomy, or TKA. Graft survival time ranged from 1 to 25xa0years based on their time to reoperation. Histologic features of early graft failures were lack of chondrocyte viability and loss of matrix cationic staining. Histologic features of late graft failures were fracture through the graft, active and incomplete remodeling of the graft bone by the host bone, and resorption of the graft tissue by synovial inflammatory activity at graft edges. Histologic features associated with long-term allograft survival included viable chondrocytes, functional preservation of matrix, and complete replacement of the graft bone with the host bone. Given chondrocyte viability, long-term allograft survival depends on graft stability by rigid fixation of host bone to graft bone. With the stable osseous graft base, the hyaline cartilage portion of the allograft can survive and function for 25xa0years or more.

The Correlation between Pes Planus and Anterior Knee or Intermittent Low Back Pain

Background: Anterior knee pain and intermittent low back pain are among the most common orthopedic complaints of adolescents. However, little is known about pes planus and its relative risk for these symptoms. The goal of the study was to track the prevalence of pes planus in adolescents, and examine its associated risk to anterior knee pain and intermittent low back pain, respectively. Materials and Methods: A retrospective study of 97,279 military recruits presenting to recruitment centers was conducted. Pes planus was graded by an orthopedist as mild, moderate or severe according to the flattening of the plantar arch and its rigidity to standing on ones toes. Anterior knee pain was diagnosed when symptoms were attributed to the patellofemoral joint. Intermittent low back pain was diagnosed when there was pain but neither abnormal clinical nor radiographic findings. Results: Pes planus was present in 15,698 (16%) individuals. 11,549 (74%), 3,341 (21%) and 808 (5%) were diagnosed as having mild, moderate and severe pes planus, respectively. The prevalence of intermittent low back pain was 5% in both the control and mild pes planus groups, while it was 10% in the moderate and severe pes planus groups (p < 0.0001). The prevalence of anterior knee pain was 4% in both the control and mild pes planus groups, while it was 7% in the moderate and severe pes planus groups (p < 0.0001). Conclusion: Moderate and severe pes planus was associated with nearly double the rate of anterior knee pain and intermittent low back pain, while mild pes planus was associated with no higher rate for these problems. Prophylactic measures may be helpful only in those adolescents with moderate and severe pes planus.

Revision Total Knee Arthroplasty for Component Malrotation is Highly Beneficial: A Case Control Study

Component malrotation is a recognized cause of post total knee arthroplasty (TKA) pain. We reviewed 24 patients who had TKA revision due to component malrotation as the only objective abnormality. Mean combined component rotation was 6.8° excessive internal rotation, as documented by computed tomography. Twenty-four matched control patients had TKA revision due to aseptic loosening. Mean follow-up was 37 months. Preoperative Knee Society Score improved by 49 points at 6 months postoperatively for the malrotation patients and by 39 for the loosening patients. At last follow-up, Knee Society Score was 80 for the malrotation group and 75 for the loosening group. We recommend the use of computed tomography scans in evaluation of all patients with early painful TKAs and no objective evidence of infection. When component malrotation is demonstrated, early revision should be considered.

Modified Trochanteric Slide for Complex Hip Arthroplasty Clinical Outcomes and Complication Rates

The sliding trochanteric osteotomy preserves vastus lateralis continuity with the osteotomized greater trochanter (GT) and the abductors. The modified trochanteric sliding osteotomy (MTSO) also preserves the posterior capsule and external rotators to reduce the risk of dislocations. The purpose of this study was to evaluate our clinical and radiographic results of the MTSO exposure. Eighty-three MTSOs were reviewed. Follow-up range was 12 to 126 months. Seventy osteotomies (84.4%) healed with bony union, 9 (10.8%) had fibrous union, and 4 (4.8%) had nonunion. There was no correlation between the width of the osteotomy, intraoperative fragmentation of the GT, or the type of femoral component and the rate of union. Six (7.2%) patients developed a new abductor lurch. Patients with union of the GT had 2.8% of a lurch, and patients with either fibrous union or nonunion had a 30.7% of a lurch (P < .05). There were 4 (4.8%) postoperative dislocations. The benefits of MTSO have been well described, and this study provides evidence of an acceptably low complication rate.

Serum levels of BMP-2, 4, 7 and AHSG in patients with degenerative joint disease requiring total arthroplasty of the hip and temporomandibular joints.

To date, there is no objective or reliable means of assessing the severity of degenerative joint disease (DJD) and need for joint replacement surgery. Hence, it is difficult to know when an individual with DJD has reached a point where total arthroplasty is indicated. The purpose of the present study is to determine whether serum levels of Alpha‐2 HS‐glycoprotein (AHSG) as well as bone morphogenetic proteins (BMP‐2, 4, 7) can be used to predict the presence of severe DJD of the hip and/or temporomandibular joint (TMJ) (specifically: joints that require replacement). A total of 30 patients scheduled for arthroplasty (diseased) (15 HIP, 15 TMJ) and 120 age‐matched controls (healthy/non‐diseased) were included. Blood samples were collected from all patients ≥8 weeks after the last arthroplasty. Concentrations of serum analytes were measured using enzyme‐linked immunosorbent assays, and these were compared between the Diseased and Healthy groups, utilizing the Mann–Whitney U‐test. Patients with disease had significantly higher levels of BMP‐2 and BMP‐4 and lower levels of AHSG in serum compared to non‐diseased humans (pu2009<u20090.01). Higher levels of BMP‐2, 4 and reduced levels of AHSG appear to characterize patients who have DJD that is severe enough to require total joint replacement. Perhaps measurements of these proteins can be used to make objective decisions regarding the need for total arthroplasty as opposed to the current subjective approaches.

Proximal femoral allograft in revision hip surgery with severe femoral bone loss: a systematic review and meta-analysis.

This study provides an objective appraisal of available evidence regarding the outcome of proximal femoral allograft for reconstruction of massive proximal femoral bone loss. The primary outcomes were rates of success, structural failure, and infection. A systematic literature review identified 16 studies with a minimum 2-year follow-up. Estimated pooled effect analysis performed with heterogeneity quantified using I(2) and τ(2). The total cohort included 498 patients with a mean follow-up of 8.1 years. The pooled success rate was 81%, pooled structural failure rate of 15%, and pooled infection rate of 8%. Significant heterogeneity was observed in structural failure rates (I(2) = 47.9, τ(2) = 0.29, P < .05). Proximal femoral allografts afford viable reconstruction for massive femoral bone loss when performed by experienced.

A Modified Cement Spacer Technique for Infected Total Hip Arthroplasties With Significant Bone Loss

Complications related to femoral spacers are common during addressing infected total hip arthroplasties by 2-stage revision. We evaluated 11 patients who had 2-stage revisions with massive bone loss after removal of the infected components by a trochanteric osteotomy. All femoral cement spacers were assembled on intramedullary nails. Femurs were protected by a plate, whereas acetabuli were augmented by a cage or roof ring depending on the remaining bone stock. This additional hardware was covered with antibiotic-impregnated cement. Infection was eradicated in 10 (90.9%) of 11 patients within 3.5 months in average. None of the patients had spacer fracture, periprosthetic fracture, or dislocation. Augmentation by hardware covered with antibiotic-impregnated cement is effective and may reduce complications until definitive treatment is performed.

Role of Cages in Revision Arthroplasty of the Acetabulum

➤ The outcome of acetabular revision is heavily influenced by the degree of associated bone loss.➤ Uncemented hemispherical acetabular components can be used in the majority of acetabular revisions, although occasionally the degree of bone loss precludes the stability of the hemispherical component at the correct anatomic level or there is minimal bleeding host bone left for biologic fixation.➤ Massive acetabular bone loss resulting in the need for bone grafts or highly porous augments involving more than half of the acetabulum is one of the main indications for the use of cages.➤ The cup-cage reconstruction is based on bone-grafting the deficient acetabulum and securing a hemispherical, highly porous metal component with multiple screws to bridge the discontinuity and off-loading the hemispherical component with a titanium cage spanning from ischium to ilium.➤ In addition to managing pelvic discontinuities, the cup-cage construct can also be used in hips without discontinuity as the hemispherical, highly porous metal component is used to restore bone stock.➤ In situations in which there is not enough bleeding host bone to secure a hemispherical component, a highly porous metal augment can be used to address the osseous deficiency. The augment is also protected with a cage to assist bone ingrowth.

The Outcome of Modified Extended Trochanteric Osteotomy in Revision THA for Vancouver B2/B3 Periprosthetic Fractures of the Femur

We hypothesised that a modified ETO in patients undergoing revision total hip arthroplasty (THA) for treatment of Vancouver B2/B3 peri-prosthetic fractures would be associated with good clinical outcomes. A retrospective review was conducted of 34 patients (mean age 73 years). At mean follow-up of 57 months, the ETO had healed in all patients. Two patients had subsidence of the femoral stem at two and three years postoperatively requiring revision, and one patient had a dislocation 3 months after surgery. The mean Harris Hip Score at the time of the final follow-up was 76.9 (range, 46-95); 23/34 patients had an excellent result, 7/34 a good result, and 4/34 a poor result. We conclude that satisfactory outcomes can be obtained using this technique.

Above Knee Amputation Following Total Knee Arthroplasty: When Enough Is Enough

In some cases, above knee amputation (AKA) for a chronically infected total knee arthroplasty is the only option. The purpose of this study was to assess patient satisfaction following AKA and to identify factors which may be indicative of successful outcome following AKA. A review was performed of 7 patients who underwent an AKA for a recurrent peri-prosthetic knee infection. Patient satisfaction was gauged through a modified questionnaire. All patients were satisfied with their AKA and 6 of 7 stated that they would have chosen an amputation earlier. Greater than 6 attempts at limb-salvage and failed gastrocnemius flap were identified by expert opinion as possible poor prognostic factors. Despite poor function, patients with chronically infected TKAs are satisfied following an AKA.