Philippe Hernigou

Treatment of osteonecrosis with autologous bone marrow grafting.

Core decompression with bone graft is used frequently in the treatment of osteonecrosis of the femoral head. Many different techniques have been described. In the current series, grafting was done with autologous bone marrow obtained from the iliac crest of patients operated on for osteonecrosis of the hip. The results of a prospective study of 189 hips in 116 patients treated with core decompression and autologous bone marrow grafting are reported. Patients were followed up from 5 to 10 years. The outcome was determined by the changes in the Harris hip score, by progression in radiographic stages, and by the need for hip replacement. The bone marrow was harvested with the patient under general anesthesia. The usual sites were the anterior iliac crests. The aspirated marrow was reduced in volume by concentration and injected into the femoral head after core decompression with a small trocar. When patients were operated on before collapse (Stage I and Stage II), hip replacement was done in nine of the 145 hips. Total hip replacement was necessary in 25 hips among the 44 hips operated on after collapse (Stage III and Stage IV). To measure the number of progenitor cells transplanted, the fibroblast colony forming unit was used as an indicator of the stroma cell activity. Patients who had the greater number of progenitor cells transplanted in their hips had better outcomes.

Stem Cell Therapy for the Treatment of Hip Osteonecrosis: A 30-Year Review of Progress

Avascular necrosis of the femoral head is caused by a multitude of etiologic factors and is associated with collapse with a risk of hip arthroplasty in younger populations. A focus on early disease management with the use of stem cells was proposed as early as 1985 by the senior author (PH). We undertook a systematic review of the medical literature to examine the progress in cell therapy during the last 30 years for the treatment of early stage osteonecrosis.

Revisiting high tibial osteotomy: fifty years of experience with the opening-wedge technique.

Since the first description by Debeyre of medial opening-wedge high tibial osteotomy proximal to the tibial tuberosity in 1951 and with the publication of our results in the English-language literature in 19871, our orthopaedic department has performed this osteotomy in 3756 patients over a period of more than fifty years. Although the opening-wedge osteotomy is not new, the advantages of the opening-wedge as compared with a closing-wedge technique have been discussed only recently, particularly in the English-language literature2-9. The aim of the present report is to describe (1) the key steps in the surgical technique, (2) the determination of the size of the wedge, (3) the improvements in the technique during the past twenty years, (4) the specific problem of posterior slope and patella baja, and (5) the technique of concomitant total knee arthroplasty and opening-wedge tibial osteotomy to avoid the need for soft-tissue release in knees with severe varus deformity.nn### Source of FundingnnNo funds were received in support of this study.nn### Initial ExposurennA longitudinal incision is made from the medial border of the patellar tendon distally along the medial aspect of the tibia for 10 cm. The insertions of the sartorius, gracilis, and semitendinosus muscles are divided, and the tendons are separated from bone as described previously1. The pes anserinus is incised longitudinally, 0.5 cm medial to its attachment to the tibia; if only moderate valgus is required, the incision can be incomplete. The distal portion of the superficial medial collateral ligament is exposed and is separated from bone proximally as far as the level of the osteotomy, which should be started at least 3.5 cm distal to the medial joint line and directed laterally and proximally toward the tip of the fibula. The posterior compartment is opened at the level of the osteotomy …

Ceramic-on-ceramic Bearing Decreases the Cumulative Long-term Risk of Dislocation

BackgroundIt 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/purposesWe 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.MethodsOne 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 27xa0years. We measured cup position, creep and wear, and capsular thickness in the hips that had revision.ResultsAL/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, 4.5xa0mm; range, 3–7xa0mm) compared with the thinnest (mean, 1.2xa0mm; range, 0.2–2xa0mm) capsule of AL/PE hips.ConclusionsAL/AL bearing couples decreased the cumulative risk of dislocation as compared with AL/PE bearing couples.Level of EvidenceLevel II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

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

PurposeTotal 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.MethodsBetween 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 75xa0years (range 65–85). All patients were followed for a minimum of fivexa0years 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.ResultsFor patients without retentive cups, the cumulative risk of a first-time dislocation was 5xa0% at onexa0month and 12xa0% at onexa0year and then rose at a constant rate of approximately 1xa0% every year to 16xa0% at fivexa0years. For patients with retentive cups, the cumulative risk of a first-time dislocation was 1xa0% at onexa0month, 2xa0% at onexa0year and then did not changed at fivexa0years. 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 (10xa0% for recurrent dislocation) compared with 1xa0% 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 80xa0years old or more (as compared with those who were less than 80xa0years 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.ConclusionWith 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.

Does primary or secondary chondrocalcinosis influence long-term survivorship of unicompartmental arthroplasty?

BackgroundCoexistence of degenerative arthritis and calcium pyrophosphate dihydrate (CPPD) crystals (or radiological chondrocalcinosis) with osteoarthritis (OA) of the knees is frequent at the time of arthroplasty. Several studies suggest more rapid clinical and radiographic progression with CPPD than with OA alone. However, it is unclear whether chondrocalcinosis predisposes to higher risks of progression of arthritis in other compartments.Question/purposesWe questioned whether chondrocalcinosis influences clinical scores, degeneration of other compartments, rupture of the ACL, survivorship, reason for revision, or timing of failures in case of UKA.MethodsWe retrospectively reviewed 206 patients (234 knees) who had UKAs between 1990 and 2000. Of these 234 knees, 85 had chondrocalcinosis at the time of surgery and 63 of the knees subsequently had radiographic evidence of chondrocalcinosis observed during followup. We evaluated patients with The Knee Society rating system and compared function and radiographic progression in the other compartments of patients without and with chondrocalcinosis.ResultsThe use of conventional NSAIDs, radiographic progression of OA in the opposite femorotibial compartment of the knee, failure of the ACL, and aseptic loosening did not occur more frequently among patients with chondrocalcinosis. The 15-year cumulative survival rates were 90% and 87% for the knees without and with chondrocalcinosis, respectively, using revision to TKA as the end point.ConclusionOur findings show chondrocalcinosis does not influence progression and therefore is not a contraindication to UKA.Level of EvidenceLevel II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

High Dislocation Cumulative Risk in THA versus Hemiarthroplasty for Fractures

BackgroundAlthough not all elderly patients with femoral neck fractures are candidates for THA, active, mentally competent, independent patients achieve the most durable functional scores with THA compared with hemiarthroplasty. However, a relatively high frequency of early or late dislocation could reduce the potential benefits with THA.Questions/purposesWe asked whether the incidence of first-time, recurrent dislocation, and revision differed in patients with hip fractures having THA or hemiarthroplasty.Patients and MethodsWe retrospectively reviewed 380 patients with hip fractures (380 hips) who underwent THAs between 1995 and 1999, and compared them with 412 patients with hip fractures (412 hips) who underwent hemiarthroplasties between 1990 and 1994. The mean followup was 8xa0years (range, 1–20xa0years).ResultsTHA had a higher early risk of first-time dislocation and a higher late risk: 19 (4.5%) of the 412 hips treated with hemiarthroplasty had at least one dislocation whereas 30 (8.1%) of the 380 hips treated with THA had at least one dislocation. The cumulative number of dislocations at the most recent followup (first time and recurrent dislocations) was 58 (13%) for the 380 THAs and 22 (5%) for the 412 hemiarthroplasties. At the 10-year followup, eight THAs (2%) had revision (six recurrent dislocations, two loosenings), and 42 hemiarthroplasties (10%) had revision (40 acetabular protrusions, one recurrent dislocation).ConclusionsThe risk of revision for recurrent dislocation increases with THA, but it remains lower than the risk of revision for wear of cartilage and acetabular protrusion in hemiarthroplasty.Level of Evidence Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Dual-mobility implants prevent hip dislocation following hip revision in obese patients

PurposeRevision total hip arthroplasty (THA) is associated with increased rates of dislocation in obese patients. It is not known whether dual-mobility implants decrease dislocation in these patients with obesity.MethodsWe retrospectively reviewed two groups of revision THAs to compare the dislocation rate between 32 obese patients (BMIu2009>30xa0kg/m2) with standard cups, and 35 obese patients (BMIu2009>30xa0kg/m2) with dual-mobility cups. All patients received the same implants except for diameter head (32-mm head with standard cups and 28-mm head with dual mobility) and had the same cemented stem that was not changed at revision. The patients were followed at routine intervals and were specifically queried about dislocation. The two groups were similar in terms of age, gender, causes of revision and follow-up since the primary arthroplasty.ResultsWith standard liners, more hips in obese patients dislocated than did hips in obese patients who received dual-mobility implants. The number of dislocations in standard hips was at one year follow-up 15.6xa0% (5 of 32) compared with 0xa0% in dual-mobility hips and was at five year follow-up 21.8xa0% (7 of 32) compared with 2.8xa0% (1 of 35). After a mean follow-up of sevenxa0years no cases of loosening were found. Five patients in the obese group with a standard liner underwent re-revision surgery, the additional re-operations being necessary to treat recurrent postoperative dislocation.ConclusionsObese patients should be counselled about the important risk of dislocation that occurs with standard liners after revision THA. Dual-mobility liners in these patients with hip revision is an efficient technique to prevent post-operative hip dislocation.

History of internal fixation with plates (part 2): new developments after World War II; compressing plates and locked plates

The first techniques of operative fracture with plates were developed in the 19th century. In fact, at the beginning these methods consisted of an open reduction of the fracture usually followed by a very unstable fixation. As a consequence, the fracture had to be opened with a real risk of (sometimes lethal) infection, and due to unstable fixation, protection with a cast was often necessary. During the period between World Wars I and II, plates for fracture fixation developed with great variety. It became increasingly recognised that, because a fracture of a long bone normally heals with minimal resorption at the bone ends, this may result in slight shortening and collapse, so a very rigid plate might prevent such collapse. However, as a consequence, delayed healing was observed unless the patient was lucky enough to have the plate break. One way of dealing with this was to use a slotted plate in which the screws could move axially, but the really important advance was recognition of the role of compression. After the first description of compression by Danis with a “coapteur”, Bagby and Müller with the AO improved the technique of compression. The classic dynamic compression plates from the 1970s were the key to a very rigid fixation, leading to primary bone healing. Nevertheless, the use of strong plates resulted in delayed union and the osteoporosis, cancellous bone, comminution, and/or pathological bone resulted in some failures due to insufficient stability. Finally, new devices represented by locking plates increased the stability, contributing to the principles of a more biological osteosynthesis while giving enough stability to allow immediate full weight bearing in some patients.

Osteogenic progenitors in bone marrow aspirates have clinical potential for tibial non-unions healing in diabetic patients

PurposeThere is a significantly higher incidence of delayed unions, non-unions, and increased healing time in diabetic patients compared with non-diabetic patients. Studies suggest that diabetics suffer from deficiencies of pancreatic stem/progenitor cells, and a clinically relevant question arises concerning the availability and functionality of progenitor cells obtained from bone marrow of diabetics for applications in bone repair.MethodsWe have evaluated the cellularity and frequency of osteogenic mesenchymal stem cells (MSCs) in bone marrow from 54 diabetic patients (12 with type 1 and 42 with type 2) with tibial non-unions. These patients were treated with bone marrow MSCs (BM-MSCs) delivered in an autologous bone marrow concentrate (BMC). Clinical outcomes and marrow cellularity were compared to 54 non-diabetic, matched patients with tibial non-unions also treated with BMC.ResultsAfter adjusting for age and sex, no differences were identified with respect to bone marrow cellularity and MSC number among the diabetic and non-diabetic groups and both groups received approximately the same number of MSCs on average. BMC treatment promoted non-union healing in 41 diabetic patients (76xa0%) and 49 non-diabetic patients (91xa0%), but the non-diabetic patients healed more quickly and produced a larger volume of callus.ConclusionWe recommend that diabetic patients be treated with an increased number of progenitor cells by increasing the bone marrow aspiration volume. We also anticipate a need to extend the time of casting and non-weight bearing for diabetic patients as compared with non-diabetic patients.