Increasing demand for total hip and total knee arthroplasty in an era of economic uncertainty and shrinking budgets has put pressure on surgeons to deliver excellent results and early functional recovery with shorter hospital stays. Patients receiving these operative interventions tend to be younger and more active. Their ultimate source of information is the Internet, which may be compromised by low quality, non-peer reviewed information, or information not at an appropriate reading level for comprehension by lower literacy individuals. Unfortunately, not all patients undergoing total hip and total knee arthroplasty are satisfied with their operative intervention. The most significant etiology of this dissatisfaction is reported to be lack of clarification and alignment of expectations between the surgeon and the patient, which may result from misinformation or lack of understanding by the patient. Furthermore, in the era of rapid recovery, length of stay has significantly decreased from 3–5 days a decade ago, now down to 1–2 days, and in some cases same day surgery. In an effort to mitigate this compromise in communication, we have developed a set of frequently asked questions and responses. These are divided into preoperative questions, perioperative questions, and postoperative questions. These are part of our patient educational materials and provide both office and hospital staff with structured responses to avoid miscommunication and misinformation. We have found it to be imperative that all information provided by the office and hospital have a consistent message.

Introduction:

Patient expectations have escalated over the past several decades with respect to demand for success with total knee arthroplasty (TKA). It is reported that 15% to 20% of TKA recipients are unsatisfied with their result. Dynamic fluoroscopic studies and gait analyses have demonstrated that patients with TKA do not exhibit normal kinematics. On the other hand, patients with partial knee arthroplasty demonstrate more normal kinematics, thought to be secondary to retention of the anterior cruciate ligament (ACL) along with the posterior cruciate ligament (PCL). While not a new concept, bicruciate-retaining designs in TKA that preserve the natural ligament structure of the knee are drawing renewed interest as an option for patients with higher and more complex activity demand. These designs may result in a more natural kinematic feel as perceived by the patient. In a study of 2313 knees in patients undergoing primary knee arthroplasty at our center, the ACL was observed to be intact in 80% and normal in 53%. Bi-cruciate retaining TKA has recently been re-introduced for use in patients with an intact ACL and PCL. As with the introduction of any new technology into orthopaedic surgery, there is a concern regarding learning curve and adverse outcomes. Therefore we review and describe our initial experience with bi-cruciate retaining TKA.

As an increasing number of young, active, large patients are becoming candidates for total hip replacements, there is an increasingly urgent need to identify arthroplasties that will be durable, highly functional and amenable to possible future successful revision. In an era when cemented femoral stems were the primary implant option, the concept of a surface replacement was attractive and, perhaps, appropriate. However, cementless femoral stems of many designs now provide dependable long-term fixation and excellent, near normal function in patients of all ages, sex and level of activity.

However, a number of issues related to cementless stem fixation could be further improved: Optimization of load transfer to proximal femur to minimise fracture risk and maximise bone preservation; Elimination of proximal-distal mismatch concerns, including bowed femurs; Facilitation of femoral stem insertion, especially with MIS THA exposures; Facilitation of revision with implants capable of providing durable fixation for active patients.

The potential benefits of short stem femoral THA implants include: Ease of insertion; Reproducibility of insertion; Avoidance of issues related to proximal-distal anatomic mismatch or variations in proximal femoral diaphyseal anatomy (e.g. femoral bowing); Facilitation of MIS surgical approaches, especially anterior exposures; Optimization of proximal femoral load transfer with consequent maximization of proximal bone preservation.

The purpose of this presentation is to describe the design rationale and characteristics of short (<115mm) uncemented primary THA femoral stem, to evaluate the clinical and radiographic results of short stems and to discuss the possible drawbacks specific to the use of short stems.

Patient expectations have escalated over the past several decades with respect to demand for success with total knee arthroplasty (TKA). It is reported that 15 to 20% of TKA recipients are unsatisfied with their result. Dynamic fluoroscopic studies and gait analyses have demonstrated that patients with TKA do not exhibit normal kinematics. On the other hand, patients with partial knee arthroplasty demonstrate more normal kinematics, thought to be secondary to retention of the anterior cruciate ligament (ACL) along with the posterior cruciate ligament (PCL). While not a new concept, bi-cruciate retaining designs in TKA that preserve the natural ligament structure of the knee are drawing renewed interest as an option for patients with higher and more complex activity demand. These designs may result in a more natural kinematic feel as perceived by the patient. This surgical demonstration will outline patient selection criteria and illustrate the technique for performing ACL- and PCL-preserving, bi-cruciate retaining TKA.

While short stem designs are not a new concept, interest has surged with increasing popularity of less invasive techniques. If the goal of the tapered stem is to load preferentially proximally, why do we need a stem at all? Perhaps the only reason to use a tapered, long stem is to prevent varus; however, studies have shown that varus malalignment of a tapered stem does not affect results. Short stems are easier to insert, especially when using an anterior approach such as the anterior supine intermuscular in which the proximal femur is elevated anteriorly from the wound during stem insertion. Femoral preparation can be accomplished with straightforward broaching of the canal, without use of reamers. Short stems are bone conserving. They violate less femoral bone stock, providing more favorable conditions should a revision be required. However, ease of insertion and bone conservation matter little if not supported by clinical results. Thus, we reviewed our early experience with 2094 patients undergoing 2457 primary THA using short, tapered titanium, porous plasma spray-coated femoral components since January 2006 at our center. The TaperLoc Microplasty stem (Biomet, Warsaw, IN) has been used in 1881 THA, and the TaperLoc Complete Microplasty stem (Biomet) in 576. Patient age averaged 63.6 years. Increased offset was used in 1990 hips (81%). The surgical approach was less invasive direct lateral (LIDL) in 1194 THA (49%), anterior supine intermuscular (ASI) in 1117 (46%), and standard direct lateral (Std) in 146 (6%). Follow-up averaged 20 months. Thirty-five stems (1.4%) have been revised: 15 for infection (12 LIDL, 3 ASI), 1 same day revision for intraoperative femoral shaft perforation (Std), 1 at 3 days for patellar dislocation (LIDL), 2 for early subsidence (1 LIDL, 1 ASI), 13 for periprosthetic femoral fracture (1 Std, 12 ASI), 2 for aseptic loosening (1 LIDL, 1 ASI), and 1 stem well fixed (ASI) removed for loose cup and unable to disarticulate trunnion.

What lessons have we learned? First, we usually require one or two diameter sizes larger with short porous tapered stem versus the standard length version of the same design. The surgeon should be aggressive with sizing, pushing to the largest size possible. Use the broach like a rasp. Drive the component in valgus during insertion. Upon seating the component, do a trial reduction using the shortest available neck length. The component will generally sit slightly prouder than the broach and may require additional effort to seat completely.

Conservation of existing bone stock, compatibility with soft-tissue sparing surgery, more physiologic loading of the proximal femur, and versatility with varying femoral anatomy make the short taper an attractive implant option. The tapered wedge short stem represents the natural evolution of joint arthroplasty to a smaller, less-invasive, and more efficient implant.

Previous studies examined failure mechanisms for revision TKA performed between 1986 and 2000. These studies demonstrated that a majority of failures occurred in the first few years, with a disproportionate amount for infection and implant-associated failure mechanisms. Since these studies were published, efforts have been made to improve implant performance and instruct surgeons towards best practice total knee arthroplasty techniques. Recently our center participated in a multi-center evaluation of revision TKA cases during 2010 and 2011. The purpose was to report a detailed analysis of the failure mechanism and the time to failure to determine whether the failure mechanism of primary TKA has changed over the past 10–15 years. Further, we evaluated the effect of failure mechanism on extent of revision and whether revision surgery was performed at the same location as the index procedure. We identified 844 revisions of failed primary TKA. Aseptic loosening was the predominant mechanism of failure (31.2%), followed by instability (18.7%), infection (16.2%), polyethylene wear (10.0%), arthrofibrosis (6.9%), and malalignment (6.6%). Mean time to failure was 5.9 years (range 10 days to 31 years). 35.3% of all revisions occurred less than 2 years after the index arthroplasty, with 60.2% in the first 5 years. In contrast to previous reports, polyethylene wear is not a leading failure mechanism and rarely presents before 15 years. Implant performance is not a predominant factor of knee failure. Early failure mechanisms are primarily surgeon-dependent.

Two-staged revision including removal of all components is a common approach for treatment of infected THA. However, removal of well-fixed femoral stems can result in bone loss and compromised fixation. An alternative in selected cases is partial two-stage exchange, in which the well-fixed femoral stem is left in situ, only the acetabular component is removed, the joint space is debrided thoroughly, a spacer is placed, IV antibiotics are administered during the interval, and delayed reimplantation is performed.

We recently reported our results using the technique of partial two-stage exchange of infected THA. From 2000 through January 2011 in 19 patients with infected THA treated with partial two-stage exchange including complete acetabular component removal, aggressive soft tissue debridement, retention of the well-fixed femoral stem, placement of an antibiotic-laden cement femoral head on the trunnion of the retained stem, postoperative course of antibiotics, and delayed reimplantation. Indications for this treatment included those patients whose femoral component was determined to be well fixed and its removal would result in significant femoral bone loss and compromise of future fixation. During the study period, this represented 7% (19 of 262) of the patients whom we treated for a chronically infected THA. Minimum follow-up was 2 years (mean, 4 years; range, 2–11 years). None of the 19 patients in this series were lost to followup. We defined failure as recurrence of infection in the same hip or use of long-term suppressive antibiotics.

Two patients (11%), both with prior failure of two-staged treatment of infection, failed secondary to recurrence of infection at an average of 3.3 years. There were no patient deaths within 90 days. Postoperative Harris hip score averaged 68 (range, 31–100).

As 89% of patients in this series were clinically free of infection at a minimum of 2 years, we believe partial two-stage exchange may represent an acceptable option for patients with infected THA when femoral component removal would result in significant bone loss and compromise of reconstruction. Further study is required on this approach.

Background:

Coronal malalignment occurs frequently in total knee arthroplasty (TKA) and reduces implant longevity and function. Designed to improve consistency and efficiency, patient- specific positioning guides (PSPG) generated from preoperative imaging studies represent a paradigm shift from manual instrumentation (MI) and intraoperative computer navigation.

Not all total hip arthroplasty cases are created equal is a maxim that holds true for both primary and revision scenarios. Complex cases involve patients presenting with compromised bone and/or soft tissue. For primary cases, these include hips with dysplasia, ankylosis, deformed proximal femora, protrusio acetabuli, prior hip fracture with or without failed fixation, previous bony procedures, or neuromuscular conditions. In revision surgery, complex scenarios include cases compromised by bone loss, deterioration of the soft tissues and resulting instability, periprosthetic fracture, leg length discrepancy, infection, and more recently, hypersensitivity reactions. In this interactive session, a moderator and team of experts will discuss strategies for evaluation and management of a variety of challenging hip case scenarios

The failure of any joint arthroplasty secondary to infection is devastating to both patient and surgeon. Eradication of infection is the primary treatment objective. Classic teaching has called for removal of all prosthetic components, thorough soft tissue and bone debridement and either immediate or delayed reimplantation with an interim antibiotic polymethylmethacrylate laden spacer. The presence of a residual biofilm on implants is a rationale for component removal. Several sophisticated removal systems have been developed for the acetabulum which facilitate component removal with minimal to no bone loss. However, such systems do not exist for the femoral component. Removal of well-fixed femoral components remains a significant challenge frequently requiring extensive osteotomies which can result in bone loss and compromise of future femoral component fixation. Therefore, it would seem attractive to leave a well fixed femoral component in situ and remove only the acetabular component, perform a thorough debridement, place an antibiotic laden polymethylmethacrylate spacer within the acetabulum and perform a delayed reimplantation. A retrospective analysis of our practice from 2000 to 2010 revealed nineteen patients treated with a partial radical debridement and delayed reimplantation with a minimum of two year follow-up. There were no patient deaths within 90 days. Follow-up averaged 3.9 years. Three patients expired during the study period at an average of 3.5 years post-operative. Two patients, both multiply revised with prior 2-stage treatment of infection, failed secondary to recurrence of infection at an average of 3.3 years. Our results suggest that partial radical debridement represents an acceptable option for patients with infected THA. We have employed this technique when it was deemed that removal of the femoral component would require extensive osteotomy resulting in significant bone loss and compromise of future femoral reconstruction. It has been successful 89% of the time. We are aware that further study is required and we remain cautiously optimistic regarding this treatment modality.

Stiffness after knee arthroplasty is an important complication that the orthopaedic surgeon must be prepared to manage. In some cases, patients have a low-pain threshold or unidentifiable etiologic findings with no clinical indicators of septic or aseptic failure, and no radiographic evidence of mechanical complications. Psychosocial issues are important to consider, such as patient motivation and etiologic findings related to a worker's compensation claim. For patients who fail to achieve satisfactory ROM after TKA with no identifiable cause, treatment options may be categorised as non-surgical and surgical interventions. Non-surgical interventions would be physical therapy and pharmaceutical control for pain management. Surgical interventions include non-invasive options such as manipulation under anesthesia, and invasive options such as arthroscopy and mini-arthrotomy. Manipulation under anesthesia is indicated in the TKA that has less than 90° ROM after six weeks, no progression or regression in ROM. A modified technique has evolved for patients with persistent stiffness after standard-technique manipulation. The modified technique uses epidural anesthesia continued for post-operative analgesia, hospital stay of 1–3 days, CPM for 2–3 days, and daily PT. Continuous epidural infusion with local anesthetic is administered to provide complete analgesia, but allows muscle activation to be maintained during the hospital stay. Although open revision is sometimes required, arthroscopic management may be an effective alternative in certain instances, and also is helpful in diagnosis and treatment of other conditions of the knee that include prosthetic loosening and failure, retained cement, loose bodies, and sub-clinical infections. However, the painful TKA without evidence of significant intra-articular pathologic findings does not always respond well to arthroscopic management. Another option is open arthrotomy, done mainly to excise scar tissue. A synovectomy may be done as well. The polyethylene insert may be removed and an examination of the posterior cruciate ligament (PCL) performed. If the PCL is tight, it can be released and the existing components may be retained. Sometimes the polyethylene liner may be exchanged to a lipped insert to maintain stability. Revision surgery represents another option of treatment that can provide improved results whether manipulation or arthroscopic debridement has been done (14). Revision of one or all components combined with arthrolysis continues to have a role in improvement of ROM and outcomes in the stiff TKA.

Ceramic-on-ceramic alumina bearings (ALX) have demonstrated low wear with minimal biological consequences for almost four decades. An alumina-zirconia composite (BIOLOX-DELTATM) was introduced in 2000 as an alternative ceramic. This contains well-distributed zirconia grains that can undergo some surface phase transformations from tetragonal to monoclinic. We analyzed 5 cases revised at 1–7 years to compare to our simulator wear studies. For the retrieved DELTA bearings, two important questions were

how much tetragonal to monoclinic transformation was there in the zirconia phase and

The retrieval cases were photographed and logged with respect to clinical and revision details. The DELTA balls varied from 22mm to 36mm diameters. These had been mated with liner inserts varying by UHMWPE, BIOLOX-FORTE and BIOLOX-DELTA materials. Bearing features were analyzed for roughness by white-light interferometry, for wear by SEM, for dimensions by CMM and for transfer layers by EDS technique. Surface transformations on DELTA retrievals were mapped by XRD. The four combinations of 36mm diameter BIOLOX-FORTE and BIOLOX-DELTA were studied in a hip simulator, which was run in ‘severe’ micro-separation test mode to 5 million cycles. Wear rates, wear stripes, bearing roughness and wear debris were compared to the retrieval data.

In two DELTA ball cases, there were conspicuous impingement signs, stripe wear and black metallic smears. It is to be noted that the metal transfer sites (EDS) appeared to be from the revision procedures. The retrieved balls run with alumina liners showed monoclinic phase peaking at 32% on the particular surface and internal bore. On the fracture surface of case 1, the monoclinic content had increased to 40%. Various surface roughness indices were assessed on the bearings. The polished articular surfaces averaged roughness (Sa) of the order 3 nm, representing extremely smooth surfaces. The main wear zone was only marginally rougher (5 nm). In contrast the stripe wear zones had roughness of the order 55–140 nm.

In the laboratory, the DELTA bearings provided a 3–6 fold wear reduction compared to FORTE controls. Roughness of stripes increased to maximum 113nm on controls. Roughness of wear stripes showed FORTE with the highest and DELTA with the lowest values. DELTA bearings also revealed much milder wear by SEM imaging. Phase transformations showed peaks at < 30% for both main wear zone and stripe wear sites. It is hypothesized that the concentration of monoclinic phase reached a certain level due to compression contraint imposed by the alumina matrix. With implant wear, additional tetragonal grains of zirconia are exposed and these will also transform to tetragonal. This consistency between laboratory and retrieval studies confirmed the stable nature of the bearings. The BIOLOX-DELTA combination provides optimal potential for a clinically relevant reduction in stripe wear.

With increased use of alternative bearings, surgeons have moved from utilization of 22, 26, 28 and 32mm heads to larger head diameters in total hip arthroplasty (THA). Reported benefits of large heads are enhanced stability secondary to the increased range of motion prior to impingement and the increased jump distance required for subluxation from the acetabulum.

This study evaluates the use of large diameter heads in primary THA comparing the rate of dislocation to a published study from our practice as a historic control.

Between October of 2001 and October 2008, 2015 THA with large heads were performed in 1743 patients. Femoral head sizes ranged from 36 to 60mm, with articulations consisting of metal-on-poly, ceramic-on-poly, and metal-on-metal. Operative approach was 63% less invasive direct lateral, 10% anterior supine intermuscular, and 27% standard direct lateral. In 1999 (Mallory et al., Clin Orthop Relat Res) we reported a low incidence of 12 dislocations (0.8%) in 1518 primary THA done with smaller femoral heads via a standard direct lateral approach. In the current series with large heads, follow-up averaged 22 months. There has been one dislocation requiring revision (0.05%), representing a significant reduction from our earlier report (p=0.0003). Forty additional acetabular components have been revised (2.0%), with eight related to sepsis (0.4%), 23 aseptic loosening (1.1%), six metal sensitivity (0.2%), one pseudotumor (0.05%), one failure of ingrowth (0.05%), and one acute early migration (0.05%).

The use of larger diameter heads has significantly lowered our dislocation rate in primary THA with only one occurrence observed in 2015 cases, for a rate of 0.05% at two years average follow-up.

Lateral retinacular release (LRR) may be necessary to balance the patellofemoral articulation in primary total knee arthroplasty (TKA). However, lateral retinacular release may be associated with an increased risk of patellar necrosis, loosening, perioperative bleeding, and pain.

Additionally, the need for lateral retinacular release may herald a more significant problem with implant positioning, rotation, and balance. The purpose of this study is to report the lateral retinacular release rate with a “patella friendly” femoral TKA design, and to identify if a less invasive approach is associated with reduced need for lateral retinacular release.

A retrospective review of our database identified 4667 primary TKA performed by two surgeons between October 2002 and January 2009. Beginning in 2002, a less invasive approach has been used in over 95% of primary TKA. Also beginning in 2002, the authors began using a new TKA design with a more swept back patellofemoral articulation (Vanguard Complete Knee System; Biomet). During the first two years of the study, the authors also used the Maxim Complete Knee System (Biomet). We previously reported a lateral retinacular release rate associated with the Maxim of 22%. There were 555 Maxim and 4112 Vanguard TKA performed. Lateral retinacular release with Maxim TKA was 12.8% (71/555), significantly less than that previously reported for the same implant design using a standard approach. Lateral retinacular release for Vanguard TKA was 1.8% (72/4112), significantly less than that with the Maxim TKA using either a standard or less invasive approach (p< 0.005).

Implant design, surgical technique, and a less invasive exposure combine to significantly reduce the need for lateral retinacular release in primary TKA.

Surgeons theorize smaller increments in sizing might better address different sized femurs and size differences between genders. This study examines utilisation of intermediate sized components to determine if availability affects outcomes of women and men undergoing total knee arthroplasty (TKA).

We reviewed 1903 consecutive, primary TKA in 1519 patients (64% women) performed with a single implant system. Originally, six femoral sizes were available; four intermediate sizes were added later. The system allows interchange ability of all femoral and tibial sizes and has seven constraint options. Four hundred and five TKA were done prior to intermediate size availability. In women before, 49% were 65mm, 47% 60mm, and 3% 70mm. After, 32% were 62.5mm, 21% 65mm and 8% 67.5mm. In men, 70mm was the most common representing 49% before and 41% after. The 65mm in men dropped from 29% before to 16% after and the 75mm dropped from 21% to 14%. After, 23% were 67.5mm. Minimum follow-up was two years.

When comparing women before versus after, women after had significantly better postoperative Knee Society (KS) pain (p=0.0000), clinical (p=0.003) and function scores (p=0.0000), and improvement in clinical (p=0.0000) and function scores (p=0.0001) while improvement in pain score was similar. Men done after had better postoperative KS pain (p=0.02) and function scores (p=0.002), and improvement in KS clinical (p=0.001) and function (p=0.0002) scores.

Both men and women undergoing TKA after availability of half sizes had better postoperative KS pain, clinical and functional scores, and improvement from preoperative levels compared with men and women before. We conclude a single TKA system with a wide variety of sizing and constraint options can provide consistently excellent results for both men and women undergoing TKA.

Ceramic-on-ceramic bearings (ALX: pure alumina) have been used for human hip joints for almost 40 years. However an alumina matrix composite with zirconia (AMC) was introduced in year 2000 as a high-strength ceramic with almost double the fatigue resistance (AMC = 80.5%ALZ and 18vol% ZrO2). However we have not found any retrieval studies reported for this new ceramic bearing.

Wear maps were generated on three retrieved AMC femoral heads (28 and 36mm diameters) using x-ray diffraction, roughness and SEM imaging techniques. The wear study ran a physiologically appropriate, micro-separation test on 36mm ceramic balls and liners (AMC/ALZ). Wear rates were determined for the four combinations of balls and cups (ALX:AMC) with mapping of main-wear and stripe-wear zones, surface-roughness and analysis of debris morphology. In addition, the zirconia transformation to monoclinic phase was studied in AMC bearings

The retrieval study showed for the first time the wear phenomena occurring on three retrieved AMC femoral heads (at 1, 3, 6 years). Two had been paired with alumina liners and one with a polyethylene liner. Case-1 featured a 36mm ball in an UHMWPE socket, case-2 was an intact 28mm AMC ball and case-3 had a fractured ball from an IDE study. Laser interferometry and SEM were used to image ceramic wear and x-ray diffraction for analysis of transformation in the zirconia phase. Main-wear zones, stripe-wear zones, metal contamination and sites of implant impingement were also characterized. Surface roughness and in-vivo aging were quantified for both non-worn and worn areas. The SEM studies showed well-preserved articular surfaces, some with faint parallel scratches still evident. The latter likely represented the manufacturer’s original polishing marks. Multiple stripe-wear sites were identified with roughness 25–65nm (Sa) whereas polished main-wear zones averaged very low at 2–3nm. Metal impingements sites stained black with transfer of titanium increased roughness up to 140nm. Mildly worn areas of case-2 AMC ball averaged 10% transformation in the zirconia phase (tetragonal to monoclinic). In the stripe-wear zones, the monoclinic phase increased to 30%. The taper-bore and fracture surfaces in case-3 averaged 30% to 40% monoclinic, respectively. The stripe-wear zones and black metal contamination on these retrieved 28mm balls were correlated to multiple impingement sites on the rim of the alumina liners and titanium shells.

The laboratory model produced stripe wear on the ceramic balls and liners. The AlX/AlX controls produced the highest run-in and steady-state wear rates at 6.3 and 2mm3/Mc respectively). In contrast, the AMC/AMC combination produced the lowest wear rates at 0.5 and 0.1 mm3/Mc, respectively). With hybrid ball:cup combinations (AlX:AMC; AMC:AlX) the wear rates were similar and showed a 3-fold reduction compared to controls. In hybrid pairings, the AMC ceramic wore preferentially more than its AlX counterpart, regardless if present as a ball or cup implant. Thus the AMC ball contributed 66% to AMC/AlX total wear whereas the ALZ ball contributed only 33% of the total AlZ/AMC wear.

This study appears to be the first documentation of wear in retrieved AMC bearing surfaces. In general, the AMC surfaces worn in-vivo corresponded well to our in-vitro wear model. The stripe-wear zones in AMC femoral heads had rougher surfaces and higher monoclinic transformation than the main-wear zone. Overall the AMC ceramic appeared more resistant to stripe-wear effects created by the micro-separation and impingement phenomena.

Introduction and Aims: Patellar subluxation is most troublesome and accounts for a number of complications in total knee arthroplasty. The purpose of this study is to report the incidence of need for lateral release before and after tourniquet deflation, and the effect of the tourniquet on proper patellar tracking.

Method: A total of 171 knees in 133 patients were prospectively evaluated for the need for a lateral retinacular release before and after tourniquet deflation. All knees were implanted using the same knee system. An initial group of 99 knees were evaluated with tourniquet inflation while the knee was in flexion. Tourniquet inflation with the knee in flexion versus extension was subsequently assessed in a subset group of 72 knees. The need for lateral release was determined using the rule of ‘no-thumbs’ and rule of ‘full contact’.

Results: A total of 77 knees appeared to need a lateral release before tourniquet deflation. After tourniquet deflation 27 knees required lateral release representing a 65 percent reduction in lateral release. There was no statistically significant difference (p equals 0.5506: Pearson’s chi square) when comparing the flexion/extension groups.

Conclusion: Often, the surgeon evaluates patellar tracking with the tourniquet inflated, not taking into account the effect of tourniquet pressure on the quadriceps muscle. Our findings support the hypothesis that the resulting pressure from the tourniquet impacts patellar tracking. We conclude that if patellar tracking is questionable with the tourniquet inflated, tracking should be re-assessed with the tourniquet deflated before considering a lateral release.

Introduction and Aims: Difficult primary and revision total knee arthroplasty (TKA) with constrained knee systems is becoming more common. Modular systems are critical to success. A review of 457 consecutive cases with a single knee system for difficult primary and revision TKA provides an algorithm for good results.

Method: Between July 1992 and December 2000, 457 consecutive TKA were performed at a single institution using a posterior-stabilised constrained (PSC) system. Ninety-seven cases were primary with ligamentous instability and 360 were revision cases with bone loss and instability. Sixty-two patients died during follow-up, seven were lost to follow-up.

Results: Follow-up averaged 2.5 years. Pre-operative Knee Society (KSS) and Hospital for Special Surgery (HSS) scores averaged 47.3 and 60.0 respectively, and improved to 79.0 and 75.0 (p< 0.001). Range of motion improved significantly (p< 0.001). Incidence of manipulation was 9.4 percent. Infection necessitated debridement in 4.6 percent of cases. Extensor mechanism complications occurred in 2.2 percent. Excision of the patellar component without reinsertion was highest risk. There was a 2.2 percent aseptic loosening rate and 3.0 percent failure for instability.

Conclusion: The authors describe an algorithm for long-term success using a PSC modular knee system based upon critical review of radiographic and clinical outcomes. Methods for achieving stability and fixation affect results. Appropriate augmentation for femoral and tibial deficits re-establishes the joint line and provides excellent range of motion. A step-wise approach to the patella provides durable results. Predictors of success including alignment, the joint line, managing bone loss, fixation, and extensor mechanism are reviewed.

Introduction and Aims: Periprosthetic femur fractures, severe bone loss with loosening, infection and debridements, and non-union can all result in loss of bone stock following total hip (THA) and/or total knee arthroplasty (TKA). In the multiply-operated or osteopenic patient, few options exist when bone is severely compromised. We report results of a total femoral construct to salvage the severely compromised femur.

Method: We retrospectively reviewed 59 consecutive total femurs. Revision THA and/or TKA was performed utilising a custom total femoral construct: a constrained acetabular component, proximal femoral replacement, diaphyseal segment, and rotating hinge knee. Return to ambulation, pain, functional capacity, and subsequent surgery outcomes were measured. All cases involved severe bone loss: 13 aseptic loosening of revision THA and TKA, 24 periprosthetic fractures, five failed non-unions around implants, and 17 cases of multiple debridements for sepsis.

Results: Mean age was 74 years, mean follow-up was 38 months. One peri-operative death occurred. Pain scores improved by 18 points. Average post-operative hip flexion was 90 and knee flexion 93. All but one patient achieved ambulatory capability. Four of 17 septic cases recurred, three successfully treated and one disarticulation. Three other infections occurred in the aseptic and periprosthetic groups, all treated successfully. There were five dislocations, one acetabular revision, and two knee revisions for aseptic loosening.

Conclusion: Total femoral replacement represents a viable salvage procedure for the compromised femur associated with THA and/or TKA. Rapid return to ambulating, relief of pain and improved function can be expected from this, the ultimate revision surgery.

Introduction and Aims: Successful cementless total hip arthroplasty (THA) is well documented, with increasing reports in elderly patients. Concerns exist with respect to the ability to achieve and maintain long-term cementless femoral fixation in this patient population. This study reviews the clinical and radiographic outcomes of a tapered porous femoral component in cementless THA in elderly patients.

Method: Forty-nine hips in 47 patients over 74 years of age underwent primary cementless THA with a tapered stem between April 1996 and April 2000. All femoral heads were sent to pathology. Radiographs, Harris hip scores and clinical data were evaluated. Revision status was known for all hips.

Results: Average age: 79 years, mean follow-up was 46 months. Six patients died during the study (mean 40 months) all THA unrelated. Twenty-two peri-operative variances occurred. There were no dislocations. Three irrigation and drainage procedures were performed, and no revisions. Mean post-operative HHS improved by 33, with 87 percent of patients having no or minimal pain. We identified two cases of stem subsidence to a stable position with no progressive radiolucencies. Mean length of stay was 4.5 days. One patient required intensive care, 52 percent were discharged to home. Metastatic cancer was identified in one femoral head.

Conclusion: Using revision status as an end-point, the success rate was 100 percent. No peri-operative deaths or significant orthopaedic complications were identified. Advanced age and Dorr C anatomy is not a contraindication for tapered cementless THA. The femoral head should routinely be sent to pathology.