Cell therapy versus simultaneous contralateral decompression in symptomatic corticosteroid osteonecrosis: a thirty year follow-up prospective randomized study of one hundred and twenty five adult patients.

PURPOSE: Symptomatic osteonecrosis related to corticosteroids has a high risk of progression to collapse in absence of treatment. The purposes of this study were to evaluate the results of autologous bone marrow grafting of the symptomatic hip in adult patients with osteonecrosis and to compare the results with core decompression alone in the contralateral symptomatic hip. MATERIALS AND METHODS: A total of 125 consecutive patients (78 males and 47 females) with bilateral osteonecrosis (ON) and who had both hips symptomatic and at the same stage on each side (stage I or II) were included in this study from 1988 to 1998. The volume of osteonecrosis was measured with MRI in both hips; the smaller size ON was treated with core decompression, and the contralateral hip with the larger ON was treated with percutaneous mesenchymal cell (MSC) injection obtained from bone marrow concentration. The average total number of MSCs (counted as number of colony forming units-fibroblast) injected in each hip was 90,000 ± 25,000 cells (range 45,000 to 180,000 cells). RESULTS: At the most recent FU (average 25 years after the first surgery, range 20 to 30 years), among the 250 hips included in the study, 35 hips (28%) had collapsed at the most recent follow-up after bone marrow grafting, and 90 (72%) after core decompression (CD). Ninety-five hips (76%) in the CD group underwent total hip replacement and 30 hips (24%) in the bone marrow graft group (p < 0.0001). Hips undergoing only CD were approximately three times more likely to undergo a primary THA (odds ratio: 10.0278; 95% CI: 5.6117 to 17.9190; p < 0.0001) as compared with hips undergoing an initial bone marrow grafting. For the 90 hips treated with bone marrow injection and without collapse, the mean volume of repair evaluated by MRI at the most recent follow-up was 16.4 cm3 (range 12 to 21 cm3) corresponding to a decrease of the pre-operative average volume from 22.4 cm3 (range 35-15 cm3) to 6 cm3 (range 12-0 cm3); as percentage of the volume of the femoral head, the decrease moved from 44.8 to 12%. CONCLUSION: Core decompression with bone marrow injection improved the outcome of the disease as compared with core decompression alone in the same patient.

Full weight bearing and dynamisation with Limmed® locked plate fixation accelerates bone regeneration in the volume of opening wedge high tibial osteotomy.

PURPOSE: The efficacy of immediate full weight bearing in accelerating bone regeneration after medial opening wedge high tibial osteotomy (HTO) was evaluated in patients operated with the Limmed system (locked plate fixation) that allows dynamisation of the site of the osteotomy. METHODS: A case series of 50 consecutive osteotomies performed with Limmed locked plate fixation for medial opening wedge HTO had full weight bearing immediately after the HTO; they were compared to a case-matched control series of 50 HTOs (50 patients) performed using the same implant without locked screws. Radiographs were observed at 30 days and two, three, four, five and six months after surgery. The osteotomy gap was only partially filled by a medial bone substitute leaving the lateral part unfilled. Bone surface areas of osteotomy planes were quantified and opening volumes were determined applying wedge heights. End points for evaluation included radiographic evidence of bone regeneration in the volume created by the opening of the osteotomy. RESULTS: Statistically significant differences were seen between the groups in terms of radiographic union and radiographic stability between the two groups. Patients of the Limmed group reported a shorter time for union (average four weeks difference) without loss of correction during healing. At the radiographic evaluation, there was a significant increase in osseointegration in the group with weight bearing compared to the control group without weight bearing with increased rate of speed to fill the void volume of the osteotomy. The computed tomography scan of the grafted area at four months after surgery showed no significant difference in the quality of the newly formed bone between the two groups. CONCLUSIONS: The Limmed medial opening wedge HTO system with immediate full weight bearing accelerates bone graft substitute osseointegration and bone healing as compared with controls without full weight bearing.

Percutaneous injection of bone marrow mesenchymal stem cells for ankle non-unions decreases complications in patients with diabetes.

PURPOSE: Clinical studies in diabetic patients have demonstrated that there is a high incidence of complications in distal tibia and ankle fracture treatments. One strategy to mitigate issues with wound healing and infection in diabetic patients is to use a percutaneous technique in which autologous, bone marrow-derived, concentrated cells are injected at the site of non-unions. METHODS: Eighty-six ankle non-union in diabetic patients were treated with bone marrow mesenchymal stem cells (BM-MSCs) delivered in an autologous bone marrow concentrate (BMC). Clinical outcomes of the 86 diabetic non-union patients treated with BMC were compared with 86 diabetic matched non-unions treated with a standard bone iliac crest autograft. RESULTS: Treatment with BMC promoted non-union healing in 70 among 86 diabetic patients (82.1 %) with a low number of complications. Of the 86 diabetic patients treated with iliac bone graft, 53 (62.3 %) had healing; major complications were observed: 5 amputations, 11 osteonecroses of the fracture wound edge and 17 infections. CONCLUSIONS: In diabetic patients with ankle non-unions, treatment with BM-MSCs from bone marrow concentrate may be preferable in view of the high risks of major complications after open surgery and iliac bone grafting, and improved healing rates compared with standard iliac bone autograft treatment.

Long, titanium, cemented stems decreased late periprosthetic fractures and revisions in patients with severe bone loss and previous revision.

PURPOSE: Long, cementless, femoral stem revisions are being used with increasing frequency. There is a relative lack of studies of late fractures after cementless implants, particularly in those patients who had a previous stem revision and are at higher risk for periprosthetic fracture after revision. In this paper, we review risk factors for periprosthetic fracture and revisions of long, cementless, locked stems and report implant survival compared with conventional, cemented, long-stem hip revision arthroplasties in such a group of patients. METHODS: We used data recorded in our institution. Between 1996 and 2002, 85 cementless femoral stem Aura™ (distal locked stem) prostheses were implanted in 85 patients. Of the 85 revisions with long, cementless stems, 32 were performed after one stem revision, 20 after two stem revisions and 12 after three stem revisions. Between 2003 and 2010, 124 femoral revision stems were performed in 124 patients using an extensively long, titanium femoral stem (Ceraver Osteal™). Kaplan-Meier analysis was used to determine implant survival. The Cox regression model was used to study risk factors for reoperation and revision. RESULTS: The increase in stem length corresponded to a mean of 4.5 ± 2.1 femoral canal diameters and was not significantly different (p = 0.02) between the two groups. Cardiopulmonary distress, intraoperative or postoperative complications were not significantly different between the two groups. There was an overall increased risk of pain, periprosthetic fractures and revision for the cementless prostheses compared with the cemented stems. With regard to thigh pain at the last follow-up, most patients (95 %) reported no pain in the cemented group, while 15 % of the cementless group experienced thigh pain under stress and 6 % had incapacitating pain. In the cemented group, stem re-revision was not required in any hip; there was no periprosthetic fracture; five stems had radiological loosening but in the absence of pain were not revised. Among patients of the cementless group, 21 % sustained failure or revision of their interlocked stem with periprosthetic fractures observed in 15 cases; factors which contributed significantly to a higher risk of fracture included the number of previous revisions; the average time between surgery and failure was 3.2 years after one revision, 2.8 years after two revisions, and 1.6 years after three revisions. CONCLUSIONS: The long, cementless, locked stem showed more early complications compared with recementing of long-stem prosthesis. We therefore recommend the use of cemented long stems in patients with severe bone loss and previous revision.

Hip hemiarthroplasty: from Venable and Bohlman to Moore and Thompson.

In 1939, Frederick R. Thompson of New York and Austin T. Moore of South Carolina separately developed replacements for the entire ball of the hip. These were used to treat hip fractures and also certain arthritis cases. This type of hemiarthroplasty addressed the problem of the arthritic femoral head only. The diseased acetabulum (hip socket) was not replaced. This prosthesis consisted of a metal stem that was placed into the marrow cavity of the femur, connected in one piece with a metal ball fitted into the hip socket. Bohlman and Austin T. Moore (1939) collaborated for the fabrication and implantation of a custom made 12-inch-long vitallium (metal alloy invented by Venable) femoral head prosthesis for a patient with a recurrent giant cell tumour. This prosthesis functioned well and later on influenced the development of long stem femoral head prostheses.

Anatomy of the ilium for bone marrow aspiration: map of sectors and implication for safe trocar placement.

PURPOSE: The bony anatomy of the human ilium has been well described from a qualitative perspective; however, there are little quantitative data to help the surgeon to perform bone marrow aspiration from the iliac crest in the thickest part of the ilium. The minimum thickness of the spongiousus bone in an iliac wing (transverse thickness between the two tables) is an important factor in ensuring the safe placement of a trocar between the two tables of the iliac wing. For example, with an 8-gauge (3.26 mm) trocar, one can consider that if the transverse thickness of the spongiousus bone of the iliac wing is <3 mm, it will be difficult to insert the trocar safely between the two tables. METHODS: For this study, we measured spongiousus bone thickness on 48 iliac wings to map the ilium in six sectors, which were defined by drawing lines from equidistant points spaced along the rim of the iliac crest to the centre of the hip. These sectors can be transposed in the same manner to any patient. To evaluate the risks to reach vascular or neurologic structures, 410 trocars were introduced in the different sectors of 20 iliac bones of ten cadavers. RESULTS: A map was constructed indicating the thickness of the spongiousus bone in each sector. The thickness data was used to create a map that identifies the sites where bone marrow can be obtained with a trocar of 3-mm diameter according to the thickness of the spongiousus bone. Sectors 2, 3 and 6 appear to be more favourable for accommodating a 3-mm diameter trocar. Sectors 1, 4 and 5 comprise the areas with the thinnest parts of the iliac crest, with some areas being thinner than the trocar diameter. The sector system reliably predicted safe and unsafe areas for trocar placement. In cadavers, dissection demonstrated nine vascular or neurologic lesions created when trocars were introduced into sectors 1, 5 and 6. CONCLUSION: Using the sector system, trocars can be directed away from neural and vascular structures and towards zones that are likely to contain larger bone marrow stock.

Ceramic-on-ceramic bearing decreases the cumulative long-term risk of dislocation.

BACKGROUND: It is unclear whether late THA dislocations are related to mechanical impingement or to a biological mechanism that decreases the stability provided by the capsule (eg, inflammation secondary to osteolysis). It is also unknown if alumina-on-alumina bearing couples decrease the risk of late dislocation as a result of the absence of wear and osteolysis. QUESTION/PURPOSES: We asked (1) whether the cumulative number of dislocations differed with alumina-on-alumina (AL/AL) or alumina-on-polyethylene bearings (AL/PE); (2) whether patient factors (age, sex, and diseases) affect risk of late dislocation; (3) whether mechanical factors (component malposition, penetration resulting from creep and wear) or (4) biologic hip factors at revision (thickness of the capsule, volume of joint fluid removed at surgery, histology) differed with the two bearing couples. METHODS: One hundred twenty-six patients (252 hips) with bilateral THA (one AL/AL and the contralateral AL/PE) received the same cemented implants except for the cup PE cup or an AL cup. The cumulative risk of dislocation (first-time and recurrent dislocation) was calculated at a minimum of 27 years. We measured cup position, creep and wear, and capsular thickness in the hips that had revision. RESULTS: AL/PE and AL/AL hips differed by the cumulative number of dislocation (31 with AL/PE versus four with AL/AL) and by the number of late dislocations (none with AL/AL, 28 with AL/PE). Cause of osteonecrosis, age, and sex affected the number of dislocations. The frequency of component malposition did not differ between the two bearing couples. The risk of late dislocation appeared less in AL/AL hips with increased capsular thickness (mean, 4.5 mm; range, 3-7 mm) compared with the thinnest (mean, 1.2 mm; range, 0.2-2 mm) capsule of AL/PE hips. CONCLUSIONS: AL/AL bearing couples decreased the cumulative risk of dislocation as compared with AL/PE bearing couples.

Safety of a novel high tibial osteotomy locked plate fixation for immediate full weight-bearing: a case-control study.

PURPOSE: The safety and efficacy of the novel Limmed® system (locked plate fixation) for immediate full weight-bearing after medial opening wedge high tibial osteotomy (HTO) were evaluated in patients with symptomatic varus gonarthrosis. METHODS: A case series of 85 consecutive osteotomies performed with Limmed® locked plate fixation for medial opening wedge HTO was compared to a historical matched case-control series of 85 HTOs (85 patients) performed using the same implant without locked screws. Subjects were observed at seven and 15 days and three, six and 12 months after surgery. Endpoints for evaluation included the reporting of adverse events, weight-bearing status without pain, radiographic evidence of bony union and changes in correction angle during healing. RESULTS: Statistically significant differences were seen between groups in terms of safety (thrombophlebitis), time to weight-bearing, radiographic union and radiographic stability between the two groups. Patients of the Limmed® group reported less thrombophlebitis (one versus nine), outcome with shorter time for full weight-bearing (average 45 days difference, p = 0.01) and a shorter time for union (average four weeks difference). At the one-year follow-up the post-operative hip-knee-ankle angle was 4.2° of valgus in the Limmed® group and 2° of valgus in the control group. The adjusted mean difference of 2.2° was significant (p = 0.02) and related to loss of correction during healing in the control group with difference in implant stability. The severity of pain, knee score and walking ability improved in both groups with a significant difference before the third month (quicker for Limmed® group), while at the most recent follow-up only the difference for mobility in flexion was significant. CONCLUSIONS: The Limmed® medial opening wedge HTO system represents a novel method of achieving a reliable correction while producing a stable fixation allowing satisfactory stability and bone healing with immediate full weight-bearing.

The risk of dislocation after total hip arthroplasty for fractures is decreased with retentive cups.

PURPOSE: Total hip arthroplasty (THA) has been efficacious for treating hip fractures in healthy older patients. However, in those patients with fractures a widely variable prevalence of dislocation has been reported, partly because of varying durations of follow up for this specific end-point. The purpose of the present study was to determine the cumulative risk of dislocation in these patients with fractures and to investigate if retentive cups decrease the risk of dislocation. METHODS: Between 2000 and 2005, 325 patients with neck fracture underwent primary THA using a retentive (325 hips) cup. The results of these 325 acetabular cups were compared to 180 THA without retentive cups performed for neck fractures in the same hospital between 1995 and 2000 by the same surgical team. The mean age of the 505 patients was 75 years (range 65-85). All patients were followed for a minimum of five years for radiographic evidence of implant failure. The patients were followed at routine intervals and were specifically queried about dislocation. The cumulative risk of dislocation and recurrent dislocation was calculated with use of the Kaplan-Meier method. RESULTS: For patients without retentive cups, the cumulative risk of a first-time dislocation was 5 % at one month and 12 % at one year and then rose at a constant rate of approximately 1 % every year to 16 % at five years. For patients with retentive cups, the cumulative risk of a first-time dislocation was 1 % at one month, 2 % at one year and then did not changed at five years. There were no differences in the mortality rates or in loosening rates among the treatment groups. The rate of secondary surgery was highest in the group without retentive (10 % for recurrent dislocation) compared with 1 % in the group treated with retentive cups. In absence of retentive cups, multivariate analysis revealed that the relative risk of dislocation for female patients (as compared with male patients) was 2.1 and that the relative risk for patients who were 80 years old or more (as compared with those who were less than 80 years old) was 1.5. Two underlying diagnoses occurring during follow up-cognitively impaired patients or neurologic disease-were also associated with a significantly greater risk of dislocation in absence of retentive cup. For these patients the risk was also decreased with a retentive cup. CONCLUSION: With standard cups the incidence of dislocation is highest in the first year after arthroplasty and then continues at a relatively constant rate for the life of the arthroplasty. Patients at highest risk are old female patients and those with a diagnosis of neurologic disease. Retentive cups in these patients are an effective technique to prevent post-operative hip dislocation.

Opening wedge tibial osteotomy for large varus deformity with Ceraver resorbable beta tricalcium phosphate wedges.

The results in 53 knees that had been treated by proximal tibial opening-wedge osteotomy for large varus deformity and osteoarthritis of the medial compartment were evaluated after a mean length of follow-up of ten years (range, 8-12 years). We used a porous beta-tricalcium phosphate (beta-TCP) wedge because it is resorbable and osteoinductive. All osteotomies were completely consolidated and complete osseointegration of the remnant of the beta-TCP wedge took place. However, after a mean maximum follow-up of ten years none of the cases showed complete resorption. After ten years, 40 (81%) of the 53 knees had an excellent or good result, and in 13 knees there was recurrent pain for which six had an arthroplasty. Although the results deteriorated with time, time was not the only determinant of the result. Alignment, measured as the hip-knee-ankle angle on radiographs of the whole limb that were made with the patient bearing weight, was also a determinant of long-term results. The best results were obtained in the knees that had a hip-knee-ankle angle of 183-186 degrees. In these knees, there was no pain and no progression of the arthrosis in either the medial or the lateral tibiofemoral compartment. Of the three knees that had an angle of more than 186 degrees, all five had progressive degenerative changes in the lateral compartment. In the undercorrected knees (an angle of less than 183 degrees), the results were less satisfactory, and there was a tendency toward recurrence of the varus deformity and progression of the arthritis of the medial compartment. However, when the correction was insufficient the deterioration was slow. Therefore, proximal tibial osteotomy is a very suitable operation even for patients who have gonarthrosis of the medial compartment and a large varus deformity. Although, a rigidly standardised and precise operative technique is required as well as accurate radiographic measurements of the mechanical axis of the limb because exact postoperative alignment is the prerequisite for the longest possible period of relief of symptoms after osteotomy, and this exact alignment is difficult to obtain for patients with large varus deformity.