Degree Of Laxity Research Articles

Radial Collateral Ligament Laxity of Thumb Metacarpophalangeal Joint Following Trapeziometacarpal Arthrodesis

Trapeziometacarpal (TM) arthrodesis may increase adduction motion of the thumb metacarpophalangeal (MCP) joint, causing radial collateral ligament laxity. Stability of the MCP joint is important to the long-term functional outcome after TM arthrodesis. This study assessed preoperative and postoperative radial collateral ligament laxity using dynamic radiographs to confirm whether laxity was exacerbated after surgery and examined whether there is a relationship between the fixation angle of arthrodesis and the degree of laxity. Forty-four thumbs in 33 patients who underwent TM arthrodesis and were followed for at least 5 years were studied. Dynamic radiographs in radial adduction-abduction and palmar adduction-abduction were obtained. We defined the midpoint of arc of motion as the fixation angle of arthrodesis in the radial and palmar planes. We measured the intersection angle between longitudinal axis of the first metacarpal (M1) and that of thumb proximal phalanx (P1). P1M1 angle in a palmar adduction view of dynamic radiographs reflected radial collateral ligament laxity in palmar adduction (adduction P1M1 angle). We subtracted a preoperative adduction P1M1 angle from a postoperative adduction P1M1 angle and defined its value as an exacerbated adduction P1M1 angle. Adduction P1M1 angle increased from 9° ± 5° to 18° ± 10°. The median exacerbated adduction P1M1 angle was 7°. Ten thumbs (23%) developed ulnar subluxation of MCP joint in the palmar adduction view of dynamic radiographs. Among them, two thumbs developed osteoarthritis of MCP joint (5%). Fixation angle of the arthrodesis was a mean of 35° ± 7° and 32° ± 9° in the radial arc and palmar arc planes, respectively. There was a positive correlation between increasing adduction P1M1 angle and TM arthrodesis in an increasingly palmarly abducted position. Radial collateral ligament laxity of thumb MCP joint was exacerbated after TM arthrodesis. Greater fixation angle in palmar abduction resulted in more laxity of the joint. Prognostic IV.

A New Algorithm to Treat Chronic Combined ACL/MCL Injuries: Let's Come Back to the “Rotatory Instability Test”

Background: Chronic combined medial collateral ligament (MCL) and anterior cruciate ligament (ACL) injuries are frequent. Medial residual laxity is a risk factor for ACL rerupture. It should be treated at the same time as the ACL reconstruction (ACLR) if necessary, but there are still questions surrounding the indications for abstention or surgery of the medial plan, especially for grade 2 MCL injuries of the Fetto and Marshall classification. Indications: The purpose is to come back to a simple test, the “Rotatory Instability Test” as described by Slocum and Larson in 1968 for systematic clinical examination of the knee to improve the sensitivity and accuracy of the deep MCL (dMCL) and superficial MCL (sMCL) examination and to propose a decision-making algorithm for the treatment of the chronic combined ACL/MCL injuries based on the assessment of anteromedial rotatory instability (AMRI). Technique Description: Examination of the ACL with Lachman test, anterior drawer in neutral rotation, and pivot shift test confirm the ACL injury. Valgus laxity is tested in extension and at 20° of flexion. Then, an anterior drawer test at 90° of flexion with external rotation is done (the anterior drawer in external rotation [ADER] test) allowing to identify isolated dMCL, dMCL + sMCL, or MCL + posterior oblique ligament (POL) injuries. Discussion: As persistent medial laxity is a risk factor for ACL graft failure and there is no reliable method of instrumented laxity assessment, careful clinical examination remains essential. Systematic examination of the medial side with valgus laxity testing at 0° and 20° flexion combined with the ADER test assessment of AMRI can guide treatment of the MCL injury component. Where there is no valgus laxity and the ADER test is negative, isolated ACLR is indicated. If there is significant medial laxity at 0°, this suggests combining sMCL and POL reconstruction with ACLR. Where the knee is stable at 0° but there is valgus laxity at 20° and a positive ADER test, the dMCL can be reconstructed using a gracilis graft or a combined sMCL and dMCL reconstruction can be added to the ACLR depending on the degree of laxity. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Isolated popliteus tendon injury does not lead to abnormal laxity in posterior-stabilised total knee arthroplasty

The popliteus tendon is crucial to postero-lateral stability and prone to iatrogenic injury intra-operatively. Its role in the stability of the replaced knee remains contentious. The aim of this study was to use computer navigation to quantify the effect of popliteus sectioning on the 'envelope of laxity' (EoL) offered by a posterior-stabilised (PS) total knee arthroplasty (TKA) and compare with that of the native knee. Loaded cadaveric legs were mounted on a purpose built rig. EoL was measured in 3 degrees of freedom using computer navigation. Knees were subjectively stressed in varus/valgus, internal/external rotation and anterior draw. This was performed preoperatively, during TKA and after sectioning of the popliteus tendon. Real-time data were recorded at 0°, 30°, 60° and 90° of flexion as the operating surgeon stressed the knee in 3 degrees of freedom to its subjective endpoint. Mixed-effect modelling was used to quantify the effects of intervention on degree of laxity. In all conditions, there was an increase in laxity with knee flexion. Insertion of a PS TKA resulted in increased constraint, particularly in rotation. Sectioning of the popliteus did not result in a significant increase in knee laxity to 90º of knee flexion. However, at deeper flexion angles, tendon sectioning overcame the constraints of the implant resulting in a significant increase in rotatory and varus/valgus laxity towards the native condition. These findings support the view that certain current designs of PS knee replacement can constrain the knee in flexion in the absence of postero-lateral deficiency. For this implant, isolated sectioning of the popliteus tendon did not substantially generate abnormal knee laxity.

Patient selection for skin-tightening procedures.

Noninvasive skin-tightening devices have become increasingly popular over the last decade to improve skin laxity with minimal risk and recovery time. Proper patient selection improves patient outcomes and satisfaction. There are many devices available for tightening including monopolar radiofrequency, bipolar radiofrequency, fractional radiofrequency devices, infrared devices, combined light and bipolar radiofrequency devices, and intense focused ultrasound devices. There have been shortcomings with tightening devices including inconsistent clinical outcomes. The question arises, why are there inconsistent results and variability among patient outcomes? Variability could be related to different devices, treatment protocols, body area treated, and patient selection. Patient age, degree of laxity, history of smoking, ethnicity, body mass index, and individual patient pain threshold could all possibly contribute to patient response to tightening devices. The literature does not elucidate consistently, which variables are the most important in predicting best patient response. Included is a review of the literature discussing skin tightening and patient selection.

Can we define envelope of laxity during navigated knee arthroplasty?

Functional outcomes after knee arthroplasty (TKA) remain poor. The ability to restore the soft tissue envelope intraoperatively may improve such outcomes. The aim of this study was to extend the scope of computer navigation as a tool to quantifying the envelope of laxity during subjective stress testing preoperatively and to quantify the effects of knee replacement and how it changes as a result of ligamentous failure. Loaded cadaveric legs were mounted on a purpose-built rig. Envelope of laxity was measured in 3 degrees of freedom using computer navigation. Knees were subjectively stressed in varus/valgus, internal/external rotation and anterior draw. This was performed preoperatively, during TKA and after sequential sectioning of ligaments. Real-time data were recorded at 0°, 30°, 60° and 90° of flexion. Mixed effect modelling was used to quantify the effects of intervention on degree of laxity. In all cases, there was an increase in laxity with increasing flexion or ligament sectioning. Operator and movement cycle had no effect. Insertion of a TKA showed increased stability within the joint, especially in internal/external rotation and anterior drawer. Once the PCL and popliteus were cut, the implant only maintained some rotatory stability; thereafter, the soft tissue envelope failed. This work has shown a novel way by which computer navigation can be used to analyse soft tissue behaviour during TKA beyond the coronal plane and throughout range of motion. Despite subjective stress testing, our results show reproducible patterns of soft tissue behaviour-in particular a wide range of mid-flexion excursion. It also quantifies the limits within which a cruciate-retaining TKR can maintain knee stability. This functionality may guide the surgeon in identifying and/or preventing soft tissue imbalances intra-operatively, improving functional results.

A Cross-Sectional Study Comparing the Rates of Osteoarthritis, Laxity, and Quality of Life in Primary and Revision Anterior Cruciate Ligament Reconstructions

The purpose of this study was to assess the degree of osteoarthritis, degree of laxity, and quality-of-life (QOL) scores in primary and revision anterior cruciate ligament (ACL) reconstruction. This was a cross-sectional study; 25 patients who had undergone revision ACL reconstruction with allografts were identified and compared with 27 randomly selected primary ACL reconstruction patients operated on in the same hospital in the same period with the same technique. The main outcome measure was the International Knee Documentation Committee (IKDC) radiographic osteoarthritis sum score, and secondary outcome measures were Knee injury and Osteoarthritis Outcome Score, IKDC functional outcome measures, anterior laxity, and QOL at follow-up. The median follow-up was 5.3 years for revision reconstruction patients and 5.1 years for primary reconstruction patients. Radiographic IKDC sum scores for osteoarthritis were found to be significantly worse in revision patients, with a median of 4, compared with primary patients, with a median of 1 (P = .016). Differences were found in meniscal injury (P = .02) and cartilage status (P < .001) before or at the index operation. Significantly worse outcomes were found in the following subscores of the Knee injury and Osteoarthritis Outcome Score: pain (median, 92 v 97; P = .032), symptom (median, 86 v 96; P = .015), activities of daily living (median, 94 v 100; P = .020), sport (median, 50 v 85; P = .006), and QOL (median, 56 v 81; P = .001). IKDC functional outcome measures were the same in both groups except for the pivot-shift test (P = .007). No differences were found in anterior drawer, Lachman, or KT-1000 arthrometer (MEDmetric, San Diego, CA) testing. Present-day health scores on the EQ-5D were worse for revision reconstruction patients (median, 70 v 80; P = .009). Revision reconstruction patients have more signs of osteoarthritis and worse QOL than primary reconstruction patients, even though they have comparable IKDC success rates and KT-1000 arthrometer laxity test results. Level III, retrospective comparative study.

Patient-Specific Rhytidectomy: Finding the Angle of Maximal Rejuvenation

Rhytidectomy is fundamentally an operation of tissue release and resuspension, although the manner and direction of suspension are subject to perpetual debate. The authors describe a method for identifying the angle of maximal rejuvenation during rhytidectomy and quantify the resulting angle and its relationship to patient age. Patients were prospectively enrolled; demographic data, history, and operative details were recorded. Rhytidectomies were performed by the senior author (AAJ). After complete elevation, the face-lift flap was rotated in a medially-based arc (0-90°) while attention was given to the submental area, jawline, and midface. The angle of maximal rejuvenation for each hemiface was identified as described, and the flap was resuspended. During redraping, measurements of vertical and horizontal skin excess were recorded in situ. The resulting angle of lift was then calculated for each hemiface using trigonometry. Symmetry between sides was determined, and the effect of patient age on this angle was assessed. Three hundred hemifaces were operated (147 women; 3 men). Mean age was 60 years (range, 37-80 years). Mean resulting angle for the cohort was 60° from horizontal (range, 46-77°). This was inversely correlated with patient age (r = -.3). Younger patients (<50 years, 64°) had a significantly more vertical angle than older patients (≥70 years, 56°; P < .0002). No significant intersubject difference was found between hemifaces (P = .53). The authors present a method for identifying the angle of maximal rejuvenation during rhytidectomy. This angle was more superior than posterior in all cases and is intimately related to patient age. Lasting results demand a detailed anatomical understanding and strict attention to the direction and degree of laxity.

Post-traumatic anterior impingement of the ankle

We enjoyed reading the well-illustrated report of 2 cases published by Valkering et al. [6]. They describe 2 patients with persisting anterior ankle impingement after an ankle sprain due to a web-like intra-articular fibrous band. One year after arthroscopic dissection of these bands, both patients were free of complaints. The authors and also others suggest that these transarticular fibrous strands could be induced by the intra-articular accumulation of blood after a trauma [2, 6]. Therefore, they advise that considering the aetiology of these bands, the consequence of observing one should prompt a careful inspection of the ankle joint for additional post-traumatic pathology. However, we have two comments on this article, and the conclusions of the authors should be seen in this light. We agree that anterior ankle arthroscopy is of great value in the diagnostic work-up and treatment for these post-traumatic intra-articular bands; however, the authors did not discuss that these bands should be differentiated from a distal/associated fascicle of the antero-inferior tibiofibular ligament (one of the syndesmotic ligaments). The fibres of the accessory ligament descended obliquely from the lateral, anterior, and distal borders of the tibia to the anteromedial aspect of the lateral malleolus, approximating the fibular insertion of the anterior talofibular ligament [1, 7]. The incidence of the accessory fascicle differs very widely in several studies and could be a normal finding [5]. When the band restricts plantar flexion, the diagnosis of post-traumatic anterior fibrous bundle is more probable because this accessory ligament only causes pain complaints [4]. The anatomical and pathomechanical aspects of these two pathologies differ and are interesting for the ankle arthroscopist. The diagnosis with arthroscopy and treatment with resection are, however, very similar. The second comment is concerning the pathomechanism of the pain complaints. After non-operative treatment for ankle sprains, some degree of laxity will persist [3] and this could result in contact between the talus and the band in the ankles, which showed no contact previously [1, 7]. As Valkering et al. already suggested, an arthroscopic impingement test (bending of the band caused by impingement of the talus) could be performed and an anterior abraded articular region of the talus due to the impingement could be observed [6, 7]. The authors do not know whether the band already exists before the ankle sprain and becomes symptomatic due to the laxity caused by injury of the anterior talofibular joint and the subsequent altered biomechanics of the ankle joint. Can this band also be observed in (post-traumatic) ankles without an anterior impingement syndrome?

Diagnostic value of MRI in females with stress urinary incontinence

Objective To discuss the diagnostic value of MRI in female patients with stress urinary incontinence (SUI). Methods All SUI patients underwent pelvic MRI examination.The 16 patients mean age was 58 years (range,48 -66 years),disease course was 6 years (range,2 -15 years).All patients underwent transobturator tension-free tape (TOT) procedures.The 28 volunteers with no pelvic diseases were set as control,Mean age was 45 years (range,30 -55 years). Results 28 Volunteers' urethral support ligaments appeared as low signal intensity broad linear structures in both T1 WI and T2WI images.Display rate:periurethral ligament was 89％ (25 cases) ; paraurethral ligament was 75％ (21 cases),unilateral 25％ (7 cases) ; pubourethral ligament,in each distal 100％ (near,28 cases),10％ (medium,3 cases),7％ (distal,2 cases); suburethral ligament was 100％ (28 cases). Levator ani muscle in T1WI,T2WI showed Moderate- intensity signal and the display rate was 100％.16 SUI patients showed varyious degrees of laxity and rupture of urethral supporting ligaments which occurred in one group (4 cases) or multi-group (12 cases) ligaments.The ligament laxity showed that periurethral ligament 14 cases,paraurethral ligament 2 cases and proximal pubourethral ligament 10 cases.The ligament rupture was seen in periurethral ligament 2 cases,paraurethral ligament 5 cases,pubourethral ligament 6 cases and suburethral ligament 7 cases.16 patients showed a relaxation of the levator ani muscle changes,including 4 cases with cervical and vaginal wall prolapsed. Conclusions MRI could clearly show the weak of support structures around the urethra in female SUI patients,and showed the cervical and vaginal prolapsed.Therefore,MRI may provide imaging evidence for clinical diagnosis and treatment. Key words: Urethral supporting ligament; Levator ani muscle; Urinary incontinence, stress ; Magnetic resonance imaging

North or South? Darron Gibson and the issue of player eligibility within Irish soccer

The issue of player eligibility in Irish soccer is a controversial one. When given the opportunity, players born in Northern Ireland should represent that country at senior international level. However, talented footballers from the Catholic community in Northern Ireland are defecting to the Republic of Ireland in ever increasing numbers. Motivated by a range of factors, from socio‐political beliefs to sporting pragmatism, these players benefit from a degree of laxity within FIFA’s regulations dealing with eligibility in the international arena. This issue has been given particular focus in recent times following the high‐profile defection of Manchester United’s Darron Gibson from Northern Ireland to the Republic of Ireland. Gibson’s decision was especially noteworthy as he failed to meet any of the criteria deemed necessary to permit such a move. This essay examines the role of the key actors in this process, which has resulted in Northern Ireland, a country with a limited pool of suitable personnel at this level, losing some of its most talented players to its neighbour and one of its fiercest rivals.

The use of hamstrings in anterior cruciate ligament reconstruction in patients over 40 years

Anterior cruciate ligament reconstruction is an increasingly established method even in patients over 40 years old. Recent studies with regard to this procedure used BTB transplants. We did a retrospective follow-up examination on over-40-year-old patients with anterior cruciate ligament reconstruction using hamstring transplants and compared them to a younger control group. Our hypothesis is that functional outcome after ACL-reconstruction is comparable in patients under and over 40 years of age. Retrospective follow-up examinations in 28 patients, 11 women and 17 men. The average age at the time of operation was 43.5 years (range 40-61). The average follow-up period was 30.4 months. Half of the patients had a femoral fixation in TransFix technique (Arthrex, Naples, USA), while the other 14 patients had a femoral bioscrew fixation (Arthrex, Naples, USA). Objectivity was ensured by measurements of anterior tibial translation with the rolimeter (Aircast). The functional outcome was determined by clinical scores (Tegner activity scale, Lysholm knee score, OAK score and IKDC score). The degree of arthrosis was defined on the basis of tunnelview radiographs and compared to the non-operated site. Functional results and degree of laxity was compared to a sex matched control group (mean age 28.0). The median values for the Lysholm knee score were 91.5 points (range 69-100), for the OAK score 93.5 points (range 67-100) and for the IKDC score 83.35 points (range 62.1-100). For the Tegner activity scale values of 4.5 points (range 3-8) were obtained. In the IKDC knee examination form we found normal and nearly normal values in 86% and in the OAK examination score good and very good results in 82%. Ninety-three percent had an AP side-to-side difference of <5 mm in the operated knee. Subjectively, 75% reported that they had no feeling of instability, even when practising sport. No significant correlation between functional outcome and patients' age was present. Furthermore there were no significant differences between the investigated and the younger control group. The most advanced signs of arthrosis were found in the medial compartment of the operated side (degree A: 36%; degree B: 46%; degree C: 14%; degree D: 4%). The predominantly good results and a high level of patient satisfaction show that anterior cruciate ligament reconstruction is justified even in over-40-year-old patients with persistend subjective symptomatic anterior knee instability. The indication for reconstruction should be based on individual factors such as level of activity or subjective feeling of instability rather than on a dogmatic age limit. Advanced arthrotic changes compared to the healthy side, might be due to a too long period of preoperative decision making.

Clinical evaluation of arthroscopically assisted anterior cruciate ligament reconstruction: Patellar tendon versus gracilis and semitendinosus autograft

To evaluate the clinical results of anterior cruciate ligament (ACL) reconstruction in patients with ACL-deficient knee in 2 similar groups of patients. A prospective randomized comparison of patellar tendon (PT) versus semitendinosus and gracilis tendon (STG) autografts for ACL reconstruction. Between 1994 and 1996, 85 consecutive male patients with chronic ACL-deficient knees underwent arthroscopically assisted reconstruction with either autologous PT or double-loop STG (4-strand) graft. PT grafts were used in patients with even-numbered birth dates and STG grafts for those with odd-numbered birth dates. Preoperatively, no significant differences between the 2 groups were noted with respect to age, level of activity, and degree of laxity (chi-square analysis). A standardized rehabilitation program was used for both groups postoperatively that included immediate active extension and early weight bearing and gradual flexion. Return to sports was permitted 8 months postoperatively. Assessment of the patients was carried out using a questionnaire, clinical assessment, Lysholm knee scores, the International Knee Documentation Committee scale, and radiological examination. At a mean follow-up of 81 months, there was no significant difference between the 2 groups with respect to subjective complaints (recurrent giving way, functional level) or objective laxity evaluation, including KT-1000 measurement or return to sports. Loss of extension of < or =5 degrees was greater in the PT group (12 patients, 30 %) than in the STG group (8 patients, 17 %). There was loss of flexion of < or =15 degrees in 5 patients (12 %) in the PT group and 1 patient (2.2 %) in the STG group. Anterior knee pain was recorded in 10 patients (24 %) in the PT group and 3 patients (5 %) in the STG group. The Lysholm knee score was 91.6 and 92.7 for the PT and STG groups, respectively, and the Tegner activity score decreased from 8.9 preoperatively for both groups to 7.9 for the PT group and 7.8 for the STG group. In this study, the 2 groups had comparable results in terms of patient satisfaction, activity level, and knee function. Our study showed that patellofemoral problems and loss of knee motion are more frequent in patients with PT grafts than in those with STG grafts. Level I, Randomized Controlled Trial.

Post‐operative use of knee brace in bone–tendon–bone patellar tendon anterior cruciate ligament reconstruction: 5‐year follow‐up results of a randomized prospective study

Sixty patients were prospectively randomized to brace and no-brace groups after bone-tendon-bone patellar tendon anterior cruciate ligament (ACL) reconstruction. The brace group wore a rehabilitation knee brace for 12 weeks post-operatively, while the no-brace group was mobilized immediately, and crutches were discarded 2 weeks post-operatively. The groups were comparable with respect to age, gender, time from injury to surgery and concomitant injuries. There were no differences either pre-operatively or 5 years post-operatively (80% of patients reviewed) between the groups in terms of the knee score (Lysholm), activity level (Tegner), degree of laxity or isokinetic peak muscle torque. Thus it appears that knee braces are not needed in the post-operative rehabilitation after ACL reconstruction with the patellar tendon graft.

Evaluation of the association between medial patellar luxation and hip dysplasia in cats

Objective To investigate the association between hip dysplasia (HD) and medial patellar luxation (MPL) in cats. Design Cross-sectional prevalence study. Animals 78 cats. Procedure A complete history was obtained. Cats were examined to detect MPL and HD. Radiographs of the stifle and hip joints were obtained. Hip joints were evaluated by use of Norberg angle, distraction index, and scoring consistent with that established by the Orthopedic Foundation for Animals. Results There were 43 male and 35 female cats (mean age, 2.5 years). Eleven cats had clinical signs of disease in the pelvic limbs. Medial subluxation of the patella (subgrade 1) was seen in 31 of 33 cats with otherwise normal stifle joints. Medial patellar luxation was found in 45 of 78 (58%) cats, and 35 of 45 (78%) had grade-1 MPL. Bilateral MPL was seen in 32 of 45 (71%) cats. A weak association existed between MPL and HD, because cats were 3 times more likely to have HD and patellar luxation than to have either condition alone. Concurrent MPL and HD were detected in 19 of 78 (24%) cats, and HD was diagnosed radiographically in 25 of 78 (32%) cats (19 mild, 4 moderate, 2 severe). Eighteen of the 25 cats with HD had bilateral HD. Conclusions and Clinical Relevance Clinically normal cats may have a certain degree of laxity in the stifle joint, evident as medial patellar subluxation (&lt; grade 1). There is a weak association between MPL and HD, and both conditions may develop, alone or in combination, more frequently than has been reported. (J Am Vet Med Assoc 1999;215:40-45)

The Lichtenstein open "tension-free" mesh repair of inguinal hernias.

All standard methods of hernia repair involve suturing together tissues which are not normally in apposition. This violates the basic surgical principle that tissue must never be approximated under tension and thus accounts for an unacceptable number of failures. A total reinforcement of the inguinal floor with a sheet of suitable biomaterial and the employment of a "tension-free" technique is a more effective approach. Since June 1984, 4,000 primary inguinal hernias have been repaired on an outpatient basis and under local anesthesia at the Lichtenstein Hernia Institute by the open "tension-free" technique using Marlex mesh. The patients were followed from 1 to 11 years by physician examination. The follow-up rate was 87%. There were four recurrences. The causes of recurrence and how to avoid them are herein discussed. Three of the recurrences occurred at the pubic tubercle and were caused by placing the mesh in juxtaposition to the tubercle. This error has since been corrected by overlapping the mesh at the pubic bone. One recurrence was caused by a disruption of the lower edge of the mesh from the shelving margin of Poupart's ligament. The error here was the utilization of a patch that was too narrow and therefore under tension. It became apparent that a wider patch, fixed in place with an appropriate degree of laxity, was required.

MR imaging of posteromedial and posterolateral stabilisers of the knee: anatomic basis and patterns of lesions in knee injuries.

The angular points are the ligamentous and tendinous structures that reinforce the posteromedial and posterolateral capsule of the knee and share in fixation of the posterior horns of the menisci. They are often damaged in acute injuries and this is usually associated with ruptures of the cruciate and collateral ligaments and may add to the degree of laxity. We describe the normal appearance of these structures in terms of the sectional anatomy, correlated with the lesional appearances of complete and incomplete ruptures and associated meniscal detachments as shown by clinical testing and arthrotomy findings.

Critical scrutiny of the open “tension-free” hernioplasty

Tension-free hernioplasty is rapidly gaining worldwide acceptance. Since June 1984, 3,125 consecutive adult male primary inguinal hernias have been repaired by employment of an open tension-free prosthetic repair without approximation of the margins of the defect. Since the original publication of our technique in the 1989 February issue of The American Journal of Surgery, we have encountered four recurrences. These recurrences were caused by technical errors early in our experience and have since been corrected. The purpose of this paper is to bring those errors to the attention of surgeons, as well as to suggest certain modifications to further simplify the operation. Three of the recurrences occurred at the pubic tubercle and were caused by placing the mesh in juxtaposition to the tubercle. This error has since been corrected by overlapping the mesh at the pubic bone. One recurrence was caused by disruption of the lower edge of the mesh from the shelving margin of Poupart's ligament. The error here was utilization of a patch that was too narrow and therefore under tension. It became apparent that a wider patch, fixed in place with an appropriate degree of laxity, was required.

Conservative and Medical Management of Hip Dysplasia

Hip dysplasia has been managed conservatively and medically since the initial description of this disease in 1935. However, little factual information is known about the benefits of the various forms of conservative and medical management. Nonsteroidal anti-inflammatory drugs have been a mainstay of treatment, with the only real debate being which NSAID to use. Only with the recent anecdotal reports of polysulfated glycosaminoglycan has there been any change in medical management of CHD, and this method of treatment warrants further investigation. Conservative and medical management definitely have a role in the treatment of CHD. It must be remembered, however that CHD is primarily a disease of biomechanical alterations and joint laxity, with the cartilage effects being secondary. With a great enough degree of laxity, coxofemoral incongruency, articular damage, or osteoarthritic change, conservative and medical management will not be effective. At that stage, surgical management must be considered.

Prospective evaluation of arthroscopically assisted anterior cruciate ligament reconstruction

Eighty consecutive patients with chronic laxity due to a torn ACL underwent arthroscopically assisted reconstruction with either autogenous patellar tendon or doubled semitendinosus and gracilis tendons. Reconstructions were performed on a one-to-one alternating basis. Preoperatively, no significant differences between the two groups were noted with respect to age, sex, level of activity, and degree of laxity (chi square analysis). A standard rehabilitation regimen was used for all patients after surgery including immediate passive knee extension, early stationary cycling, protected weightbearing for 6 weeks, avoidance of resisted terminal knee extension until 6 months, and return to activity at 10 to 12 months postoperatively. Seventy-two patients were evaluated at a minimum of 24 months postoperatively (range, 24 to 40 months). No significant differences were noted between groups with respect to subjective complaints, functional level, or objective laxity evaluation, including KT-1000 measurements. Seventeen of 72 patients (24%) experienced anterior knee pain after ACL reconstruction. Overall, 46 of 72 patients (64%) returned to their preinjury level of activity. Mean KT-1000 scores were 1.6 +/- 1.4 mm for the patellar tendon group and 1.9 +/- 1.3 mm for the semitendinosus and gracilis tendons group. This study did find a statistically significant weakness in peak hamstrings torque at 60 deg/sec when reconstruction was performed with double-looped semitendinosus and gracilis tendons.

The genetics of quantifiable homeostasis: I. The general issues.

Some fundamental issues in developing the quantitative genetics of heritable traits are addressed. Such a trait must be capable of being represented as a quantity. Choice of the metric can be satisfactorily made only in the light of some insight into the nature of the trait and what its revealing characteristics may be. This insight is likely to change as more is known about the process, so the form and detail of the analysis is not static but perhaps continually evolving. Much has been made out of sample means and, at a more sophisticated level, Galton-Fisher theory (the analysis of the first two moments of multivariate Gaussian variates). However, at least some processes seriously violate the assumptions underlying that theory. One such group comprises traits in which the means are unvarying and the genetic message lies in other aspects of the distribution; in these circumstances the standard summary statistics such as heritability, regression, and correlation may be totally uninformative, distracting, or even misleading. This paradox is illustrated by reference to homeostasis, where the Mendelian component lies, not in the mean, but in the degree of laxity of control. Since estimating higher moments is notoriously imprecise, the suggested remedy is the familial and commonsense one of exploring the genetics of the intermediate states and underlying mechanisms and not only that of the resultant ("bottom-line") phenotype. In our chosen problem, the task of relating the outcome to the basic mechanism of inheritance calls for a detailed understanding of the homeostasis involved.