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S David Stulberg

Publications and source records attributed to S David Stulberg.

16 recordsLinked to original sources

Total hip arthroplasty with the porous-coated anatomic hip prosthesis: results at 11 to 18 years.

The authors had previously reported good results with apparent fixation of a series of porous-coated anatomic hips at 2 to 4 years. In a larger series of 133 hips with porous-coated anatomic uncemented components, 91 hips in 82 patients were available for a follow-up of 11 years or greater. Although 3.1% of acetabular cups had migrated or had been revised at 2 to 4 years; at 11 to 18 years, there was 37% lysis, 21.7% migration, and 32.3% revision. For the femur at 2 to 4 years, there was 3.1% migration and 1.5% revision. At 11 to 18 years, there was 27.2% lysis (proximal only), 6.6% migration, and 3.2% revision. Survival analysis for migration or revision for the femoral was 94%, and for the acetabular component, 63%, deteriorating markedly after 10 years.

Adolescent↗

Computed tomographic follow-up evaluation of operative intervention for periacetabular lysis.

Computed tomography (CT) accurately evaluates periacetabular lytic lesions. The purpose of this study is to determine the fate of osteolytic lesions after treatment with liner exchange and bone grafting. Fifteen patients who had undergone liner exchange with grafting for progressive lytic lesions, as demonstrated by preoperative CT scans, were identified. Postoperative CT scans were performed at a minimum of 2 years post revision. The largest cross sectional lytic area was compared with the postoperative scan to determine the fate of the lesion. The mean size of the measured lytic lesions preoperatively was 6.38 cm(2). Postoperatively, lesions decreased to 2.94 cm(2) (P = .000). Modular liner exchange with grafting is effective in treating osteolytic lesions in the pelvis, as demonstrated by CT.

Acetabulum↗

Radiographic evaluation of a monoblock acetabular component: a multicenter study with 2- to 5-year results.

Serial radiographs of a porous tantalum monoblock acetabular cup design were evaluated for cup stability and signs of successful osteointegration. Of 574 primary consecutive total hip replacements in 542 patients performed by 9 surgeons at 7 hospitals, 414 cases were available for minimum 2-year follow-up. Follow-up averaged 33 months and ranged from 24 to 58 months. Postoperative radiographs revealed acetabular gaps in 100 zones in 80 (19%) hips: 29 in zone I, 67 in zone II, and 4 in zone III. At last follow-up, 84 (84%) of the zones with gaps completely filled in, and all 4- and 5-mm gaps filled in. There was no progression of any postoperative gap, no evidence of continuous periacetabular interface radiolucencies, no evidence of lysis, and no revisions for loosening. Although these short-term results are encouraging, further follow-up will be required to assess whether the monoblock design and the low modulus of elasticity of porous tantalum will reduce the incidence of periacetabular stress shielding and occurrence of osteolysis.

Acetabulum↗

Minimally invasive navigated knee surgery: an American perspective.

Minimally invasive total knee replacement surgery may make it possible for patients to undergo the procedure with less pain and recover from the surgery more quickly than has been previously possible. However, minimally invasive techniques have the potential for being associated with a number of complications, including implant and limb malalignment. Computer-assisted technologies used in conjunction with minimally invasive techniques allow the accuracy with which the procedures are performed to be retained.

Arthroplasty, Replacement, Knee↗

Bone loss in revision total knee arthroplasty: graft options and adjuncts.

The treatment of small bone defects in revision total knee arthroplasty should make immediate full weight bearing and full therapy possible, provide long-term stability for the implants, and restore bone stock. These objectives are achieved with bone grafts if the defects are cavitary or small (involving less than one fourth of the cortical rim) segmental defects. These objectives are achieved with porous metal augments if the defects are segmental and involve more than one fourth of the cortical rim. The treatment of bone loss on the femur must allow the re-establishment of the distal and posterior joint lines as well as provide a firm fixation base for the implants.

Arthroplasty, Replacement, Knee↗

Predicting total knee replacement pain: a prospective, observational study.

To describe the natural history of pain after total knee arthroplasty and to identify factors predicting excessive postoperative pain, we used a prospective, observational study assessing clinical and radiographic variables preoperatively and at 1, 3, 6, and 12 months after knee replacement. Data sources included the visual analog pain scale and other measures of patient health, psychologic state, and component reliability. Regression analyses were conducted to identify specific factors predictive of postoperative pain, controlling for inequality of variables, and confirmed using regression diagnostics. For 116 patients (149 knees; mean age, 66 years; 55.2% women), significant pain was reported by 72.3%, 44.4%, 22.6%, 18.4%, and 13.1%, respectively. No intergroup differences existed for anesthesia, weight, age, or gender. Patients with greater preoperative pain had more postoperative pain, used more home therapy, and postoperative manipulations. Preoperative depression and anxiety were associated with heightened pain at 1 year. Pain after knee replacement resolves quickly, declining to approximately (1/2) by 3 months. However, one in eight patients report moderate to severe pain 1 year after surgery despite an absence of clinical or radiographic abnormalities. Development of office-based preoperative screening tools and interventions for these patients may reduce postoperative costs and improve patient-perceived outcomes.

Adult↗

How accurate is current TKR instrumentation?

Mechanical total knee replacement (TKR) alignment systems have fundamental limitations that limit their ultimate accuracy. This study uses an image-free computer-assisted navigation system to assess the accuracy of a currently available conventional mechanical, intramedullary instrumentation system. Mechanical instrumentation allows reasonably accurate and reproducible (within 3 degrees varus-valgus) frontal and sagittal limb alignment. There is a tendency to leave the knee in slight flexion, to hyperextend the femoral component and to posteriorly tilt the tibial implant with mechanical AP guides. There also is a consistent tendency to internally rotate the femoral implant. Although almost all of the 20 TKRs resulted in final limb alignment within 3 degrees of the frontal and sagittal mechanical axes, only four TKRs were done in which all of the measured steps were within 3 degrees of the optimal positions. If implant longevity, pain-relief, and function are related to the accuracy with which TKRs are done, this study emphasizes that current mechanical instrumentation does not result in a high incidence of accuracy when each step of the procedure is measured. Computer-assisted techniques permit measurement of the steps of the TKRs procedure with a high degree (error < 1 degree) of accuracy.

Arthroplasty, Replacement, Knee↗

Impaction grafting: doing it right.

Impaction grafting has emerged as a useful technique in the armamentarium of the revision total hip arthroplasty surgeon. The original technique proposed by Ling has been associated with complications, including femoral shaft fractures, recurrent dislocations, and uncontrolled component subsidence. Modifications in that technique seem to be associated with a reduction in complications. The radial impaction grafting technique permits the use of revision femoral components with variable stem lengths, neck lengths, and neck offsets. The technique seeks to improve the quality of bone impaction and reduce the incidence of subsidence. Initial results have been encouraging.

Arthroplasty, Replacement, Hip↗

Use of helical computed tomography for the assessment of acetabular osteolysis after total hip arthroplasty.

BACKGROUND: Acetabular osteolysis is a major problem affecting long-term survival of total hip prostheses. Since lytic lesions may be asymptomatic until extensive bone loss has occurred, early detection of lytic lesions is important. The purposes of this study were to determine the efficacy and potential role of high-resolution helical (or spiral) computed tomography with metal-artifact minimization in the early detection of osteolysis of the pelvis and to use the method to determine if there was a relationship between the extent of osteolysis and the amount of polyethylene wear. METHODS: Forty patients (fifty hips) who had undergone primary cementless total hip arthroplasty between 1988 and 1994 were evaluated as part of an ongoing prospective study. These patients had a history of high-level activity that was believed to place them at increased risk for accelerated polyethylene wear. The most recent follow-up radiographs were compared with the three-month postoperative radiographs. Helical computed tomography scans with metal-artifact minimization were made, and evidence of osteolytic lesions on these scans was compared with that on the radiographs. Two-dimensional wear analysis was performed with use of digitized radiographs, and the results were compared with loss of bone volume as calculated from the computed tomography scans. RESULTS: Acetabular lysis was identified on the radiographs of sixteen hips and on the computed tomography scans of twenty-six hips. Radiographs underestimated the extent of the lysis in thirteen of the sixteen hips. There was no correlation (r = 0.036) between linear wear and the measured volume of bone loss, with the numbers available. On the basis of the amount of lysis seen on the computed tomography scans, one patient underwent a revision procedure. CONCLUSIONS: Helical computed tomography with metal-artifact minimization is more sensitive for identifying and quantifying osteolysis after total hip arthroplasty than is plain radiography. Since computed tomography scans show both the extent and the location of lytic lesions, they are useful to guide treatment decisions as well as to assist in planning for surgical intervention, when needed, in patients with suspected osteolysis.

Acetabulum↗