Allogeneic transplantation of selected CD34+ cells from peripheral blood: experience of 62 cases using immunoadsorption or immunomagnetic technique. Spanish Group of Allo-PBT

Disruption of the anterior cruciate ligament (ACL), a primary stabilizer of the knee, can produce disability. The purpose of our work has been to study the normal ACL in humans, in the presence of normal muscle function and body weight, and develop clinical criteria for reconstruction, establish a basis for rehabilitation programs, and evaluate how knee braces protect this important ligament. The strain behavior of the ACL has been measured by arthroscopic implantation of the Differential Variable Reluctance Transducer while subjects are under local anesthesia. Movement of the knee from a flexed to an extended position, either passively or through contraction of the leg muscles, produces an increase in ACL strain values. Isolated contraction of the dominant quadriceps with the knee between 50 degrees and extension creates substantial increases in strain. In contrast, isolated contraction of the hamstrings at any knee position does not increase strain. With the knee un-weighted, the protective strain shielding effect of a functional knee brace decreases as the magnitude of anterior shear load applied to the tibia increases. A different behavior occurs during weight bearing, the strain shielding effect of the brace remains constant as the magnitude of anterior load increases. Our approach is novel in that it can be used to measure on important portion of the ACLs strain distribution while clinically relevant loads are applied to the knee, subjects perform rehabilitation exercises, or in the presence of different orthoses such as functional knee braces.     

The effects of functional knee braces on speed in collegiate basketball players

Knee braces are worn by many athletes following injury. The purpose of this study was to determine whether two functional knee braces (noncustom design) significantly affected straight line and successive turning trial running times in noninjured collegiate basketball players. Twenty-five coed basketball players completed 2 days of running trials. Subjects ran three full lengths of a basketball court and 10 lengths between the baseline and the foul line first without wearing a brace, then wearing either a DonJoy GoldPoint brace or an Omni OS-5 brace, and finally wearing the other brace. The results indicated no significant difference (p < .05) in straight line or successive turning running times when the two braces were compared with the nonbraced condition and when the two braces were compared with each other. The results implied that speed was not significantly affected by a functional knee brace in noninjured collegiate basketball players.     

Infrapatellar contracture syndrome. Diagnosis, treatment, and long-term followup

Infrapatellar contracture syndrome is an uncommon but recalcitrant cause of reduced range of motion after knee surgery or injury. The results and conclusions presented here are based on a retrospective clinical study evaluating the long-term outcome in 75 patients who developed infrapatellar contracture syndrome. These 75 patients (76 knees) were evaluated at an average followup of 53 months after the index (inciting) procedure or injury. Comparing subgroups within the study population, factors that correlated with poorer results or more severe infrapatellar contracture syndrome were found to be acute anterior cruciate ligament repair or reconstruction, the use of patellar tendon autograft for anterior cruciate ligament reconstruction, nonisometric graft placement, multiple surgical procedures, use of closed manipulation, and the development of patella infera. We concluded that appropriate procedures can substantially increase the range of motion in patients with infrapatellar contracture syndrome. However, residual functional morbidity persists in many patients, and the outcome, as determined by subjective knee function scores, is only fair. The natural history of an anterior cruciate ligament-deficient knee appears to be more benign than the natural history of a knee that develops infrapatellar contracture syndrome.     

Correlations between clinical examination/MRI/arthroscopy in the acute traumatic knee

Authors study retrospectively 81 cases of isolated recent (less than three months) knee traumas. These include clinical aspects, NMR, arthroscopy. Clinical examinations have been graded: 1. possible lesion; 2. likely lesions; 3. confirmed lesions. Clinical examinations and NMR results are compared to arthroscopy considered as reference. Clinical examination of acute traumatic knee is essential. Nevertheless, its value for detecting precise lesions is poor, except for knee locking well correlated with meniscal tears. Results show that NMR provide better results than clinical examination. NMR is reliable for detecting tears of posterior cruciate ligament, tears of posterior horn of menisci (sensibility: 93%; specificity: 80%). Its results are less effective for appreciation of lesion of anterior cruciate ligament (sensibility: 88%; specificity: 78%) because of partial tears and functional but not morphologic damage. It is the only method able to evidence osteochondral injuries and soft-tissues associated lesions in traumatic knees. Emergency NMR scans show results no differences in results compared with routine examinations. However, one should keep in mind that negative NMR cannot exclude small cartilaginous lesions and partial tears of anterior cruciate ligament. According to these results and the known qualities of NMR (non invasive), we propose that this type of investigation should be more largely included in diagnostic attitude for acute injured knee. Emergency diagnostic arthroscopy could be efficiently replaced by NMR knee examination.     

Coronary hemodynamics in aging spontaneously hypertensive and normotensive Wistar-Kyoto rats

Conventionally, the hamstring:quadriceps strength ratio is calculated by dividing the maximal knee flexor (hamstring) moment by the maximal knee extensor (quadriceps) moment measured at identical angular velocity and contraction mode. The agonist-antagonist strength relationship for knee extension and flexion may, however, be better described by the more functional ratios of eccentric hamstring to concentric quadriceps moments (extension), and concentric hamstring to eccentric quadriceps moments (flexion). We compared functional and conventional isokinetic hamstring: quadriceps strength ratios and examined their relation to knee joint angle and joint angular velocity. Peak and angle-specific (50 degrees, 40 degrees, and 30 degrees of knee flexion) moments were determined during maximal concentric and eccentric muscle contractions (10 degrees to 90 degrees of motion; 30 and 240 deg/sec). Across movement speeds and contraction modes the functional ratios for different moments varied between 0.3 and 1.0 (peak and 50 degrees), 0.4 and 1.1 (40 degrees), and 0.4 and 1.4 (30 degrees). In contrast, conventional hamstring:quadriceps ratios were 0.5 to 0.6 based on peak and 50 degrees moments, 0.6 to 0.7 based on 40 degrees moment, and 0.6 to 0.8 based on 30 degrees moment. The functional hamstring:quadriceps ratio for fast knee extension yielded a 1:1 relationship, which increased with extended knee joint position, indicating a significant capacity of the hamstring muscles to provide dynamic knee joint stability in these conditions. The evaluation of knee joint function by use of isokinetic dynamometry should comprise data on functional and conventional hamstring:quadriceps ratios as well as data on absolute muscle strength.     

The effects of knee reconstruction on combined anterior cruciate ligament and anterolateral capsular deficiencies

We tested the effect of intraarticular reconstructions of the anterior cruciate ligament alone and in combination with extraarticular reconstructions in 10 cadaveric knees. These knees had anterior cruciate ligament deficiency alone or in combination with anterolateral capsuloligamentous deficiencies. In the knees with combined injury, intraarticular reconstruction returned anterior stability to levels not significantly different from levels found for the knees deficient in the anterior cruciate ligament alone and treated with this procedure. After intraarticular reconstruction, rotational stability of the knee with combined injuries failed to return to the levels seen in the knee with isolated anterior cruciate ligament deficiencies that underwent the same treatment. When a tenodesis with either 0 N or 22 N of tension was added to the intraarticular reconstruction in the knee with combined injuries, we found that excessive internal rotation significantly decreased at all angles of flexion, except at full extension with 0 N of tension. In addition, the extraarticular reconstruction with 22 N of tension in the tenodesis overconstrained the knee in internal rotation between 30 degrees and 90 degrees of knee flexion. The tenodesis with 0 N of tension overconstrained the knee at only 60 degrees and 90 degrees of flexion. These results suggest extraarticular reconstruction as an adjunct to the intraarticular operation for the knee with anterior cruciate ligament and anterolateral structural injuries. The results also suggest that the surgeon can affect anterior and rotational laxity by adjusting the tension in the tenodesis.     

Periosteal new bone formation in a canine neuropathic model of osteoarthritis

OBJECTIVE: To characterize, for the first time, periosteal new bone formation in a well-established canine model of accelerated osteoarthritis (OA) with features of neuropathic arthropathy. METHODS: Seven dogs underwent left L4-S1 dorsal root ganglionectomy (DRG), followed 3 weeks later by transection of the anterior cruciate ligament of the ipsilateral knee (ACLT). Eight weeks thereafter, a postmortem examination was performed to assess the severity of cartilage changes of OA and the formation of new bone on the distal femur and proximal tibia in the cruciate-deficient limb. RESULTS: As described previously, extensive full-thickness ulceration of the articular cartilage was present in the unstable knee of every dog. The femoral shaft immediately proximal to the condyles in the unstable limb was consistently wider (mean +/- SD diameter 22.4 +/- 2.2 mm) than that in the contralateral limb (19.9 +/- 1.3 mm; P = 0.01). Xeroradiography and histologic examination of the distal femur revealed extensive formation of woven bone on the periosteal surfaces of the medial, lateral, and anterior aspects of the femoral shaft in the OA limb of every dog. These bony changes were not seen in radiographs of dogs that underwent DRG with the cruciate ligament left intact (n = 8) or of neurologically intact dogs that underwent ACLT (n = 7) and were examined 24 weeks after surgery. CONCLUSION: Formation of new periosteal bone on the distal femur and tibia is a feature of this model of accelerated OA that is not seen in the conventional ACLT model of OA in the neurologically intact dog. This observation suggests that interruption of sensory input from the limb may affect the regulation of osteogenesis in the mechanically unstable joint.     

Kinematics of posterior cruciate ligament-retaining and -sacrificing mobile bearing total knee arthroplasties. An in vitro comparison of the New Jersey LCS meniscal bearing and rotating platform prostheses

The posterior cruciate ligament (PCL)-retaining, meniscal bearing and the PCL-sacrificing rotating platform designs of the LCS prosthesis (DePuy, Warsaw, IN) were designed to minimally constrain knee kinematics while minimizing bone-cement-prosthesis interface stresses and polyethylene wear. The kinematics and stability of the knee following arthroplasty with these devices rely on adequate tensioning of the remaining soft tissues by management of the flexion/extension gaps at the time of surgery. In this in vitro study, the knee kinematics of the function of the quadriceps mechanism for 8 cadaveric knees were measured quantitatively before and after implantation of these 2 prosthesis designs. Following implantation of the PCL-retaining, meniscal bearing prosthesis, anterior translations during anterior drawer testing were significantly greater (P < .05) than those seen in the intact knee. Implantation of the PCL-retaining, meniscal bearing prosthesis resulted in an increase in the extension gap of 2 mm. Quadriceps force needed to achieve full extension was increased by 30% over that needed in the intact knee. The PCL-sacrificing, rotating platform prosthesis constrained anterior translation such that nearly normal anterior knee stability was reestablished; however, the extension gap was increased by 4 mm and the quadriceps force needed to achieve full extension was 50% greater than that needed in the intact knee. Attempts to achieve joint stability by increases in the thickness of the tibial component to widen the flexion/extension gaps results in compromises of quadriceps efficiency, particularly in the absence of a functioning PCL, as demonstrated in this in vitro model. Patients receiving the PCL-sacrificing prosthesis may experience difficulty in those activities requiring quadriceps power near full extension, such as rising from a chair or ascending or descending stairs.     

Acute knee injuries: Part I. History and physical examination

A thorough history and physical examination are helpful in the diagnosis of meniscal damage, cruciate and collateral ligament sprains and patellar instability, the four major acute knee injuries. When performing a physical examination in a patient with a knee injury, the uninjured knee should always be assessed first and used for comparison. Examination includes passive and active range-of-motion testing, palpation of the joint line spaces, and a variety of maneuvers to evaluate knee stability. Valgus and varus testing provides assessment of the collateral ligaments. The Lachman and pivot shift tests are useful in the evaluation of the anterior cruciate ligament. The posterior drawer and tibial sag tests are used to evaluate the posterior cruciate ligament. The bounce test, McMurray's test and Apley's grind test can aid in the diagnosis of meniscal injury.     

Anterior cruciate ligament reconstruction and joint dynamics during stair climbing

Athletes with anterior cruciate ligament (ACL) deficiencies exert decreased knee extension moments during level walking (quadriceps avoidance gait), and yet within a few months of ACL reconstruction they are often expected to return to competitive sport. To investigate this issue further, 10 normal subjects and seven ACL deficient patients were evaluated both pre- and post-operatively (mean follow-up of 6 months), and each performed multiple trials ascending a staircase which consisted of three steps. Bilateral joint angles, moments, powers, and work were measured and the data were ensemble averaged and statistically analyzed (repeated measures ANOVA with significance level set at 0.05). Anterior-posterior knee laxity decreased significantly (from 7.9 mm to 5.8 mm) while subjective knee function also improved following ACL reconstruction (knee score increased from 70.4 to 88.5). Pre-operatively, there were no statistically significant differences in biomechanical parameters between the patients' ACL-deficient and intact sides and the normal subjects. Post-operatively, however, statistically significant reductions were seen for the peak moment (91.9 vs 22.5 Nm), power (181 vs 84 W), and work performed (28.0 vs -5.6 J) at the injured knee, which was also the knee from which the patellar tendon graft had been harvested. These reductions were accommodated by significant increases in excursion, moment, and power at the contralateral ankle joint. The results indicate that while the ACL reconstruction were successful in restoring anterior-posterior knee stability, the decrease in knee power and work performed post-operatively by the injured (i.e., donor) knee suggests that donor site morbidity may need to be critically evaluated over a long-term period.     

Outcome of hip and knee arthroplasty in persons aged 80 years and older

Recent studies have established the cost effectiveness and safety of total joint arthroplasties. As the population ages, it is important to determine whether these procedures are equally beneficial in the elderly. The short term safety and efficacy of total hip and knee arthroplasties in subjects 80 years of age and older was evaluated. Between 1988 and 1993, preoperative and postoperative physical and functional information was collected on 99 consecutive elective hip and knee arthroplasties in subjects 80 years of age or older. These data were compared with those derived from a younger otherwise matched control group. Data collected included subject demographics and characteristics, information concerning the acute and postacute hospital stay, comorbid conditions, postoperative complications, discharge disposition, Hospital for Special Surgery knee and Harris hip scores, pain scores, and functional capacity. The average age of the subjects was 83 years; osteoarthritis was the most common diagnosis; and the average followup was 25 months. Complication rates and length of stay in acute care facilities were not significantly different than for the control group. Mean preoperative Hospital for Special Surgery knee and Harris hip scores were 58 and 60, respectively, with postoperative scores of 77 and 88, respectively. Pain dramatically improved with 98% of total knee arthroplasty and 100% of total hip arthroplasty subjects reporting mild or no pain at followup. Preoperatively, none of the knee or hip subjects could walk unlimited distances. Postoperatively 51% of the total knee arthroplasty and 54% of the total hip arthroplasty subjects could walk more than five blocks; 71% of the total knee arthroplasty and 86% of the total hip arthroplasty subjects walked with a cane or no assistive device. The most dramatic postoperative functional gains were seen in the most disabled subjects. Total charges of care for patients 80 years of age and older was slightly greater than for a younger group. It was established that total joint arthroplasty can be performed safely in patients 80 years of age and older, promising excellent pain relief and improved functional outcome.     

The effect of immediate weightbearing after anterior cruciate ligament reconstruction

Immediate weightbearing has been advocated after anterior cruciate ligament reconstruction and is thought to enhance the return of quadriceps muscle activity and knee extension range of motion without jeopardizing graft integrity. This study examined the effect of immediate weightbearing after anterior cruciate ligament reconstruction on the return of vastus medialis oblique electromyography activity, knee extension range of motion, knee stability, physical examination, Lysholm score, and anterior knee pain. Forty-nine patients (24 men and 25 women) undergoing endoscopic central third patella tendon autograft reconstruction were randomized prospectively into two groups. Group 1 patients underwent immediate weightbearing as tolerated. Group 2 patients were kept nonweightbearing for 2 weeks. All measurements were taken before surgery, 2 weeks after surgery, and between 6 and 14 months (average, 7.3 months) followup. There was no effect of weightbearing on knee extension range of motion or vastus medialis oblique function at followup. In addition, knee stability was not compromised after surgery. Seven of 20 (35%) nonweightbearing patients and only two of 25 (8%) immediate weightbearing patients reported anterior knee pain at followup. Overall, immediate weightbearing did not compromise knee joint stability and resulted in a better outcome with a decreased incidence of anterior knee pain.     

Interdisciplinary concepts in treating adult patients

Pre-prosthetics, as a part of orthodontic treatment in adults has gained increasing importance during recent years. Through coordinated orthodontic, prosthetic and periodontal treatment plans, patients with partial dentition can be offered further treatment possibilities. Such planning would allow for fixed prosthetic treatment possibilities and the survival of critical teeth. They would provide for better aesthetics and avoid functional disturbances. The aim of the present study was to present reports of patients treated by coordinated work at the Dental School of Hamburg University. In patients with partial dentition, premolars were uprighted and distally moved and molars were extruded to be used as abutments for fixed prosthetic reconstructions. Following trauma, the position of the remaining anterior teeth was improved to provide for optimal aesthetics after prosthetic treatment. Extraction of a subalveolarly fractured tooth is avoided through root extrusion and post-core reconstruction. The results demonstrate the advantages of pre-prosthetic treatment as regards stability, aesthetics and function. With the help of pre-prosthetic orthodontic treatment, complicated treatment situations could be handled more successfully than would have been the case without such treatment.     

Restoration of gait by functional electrical stimulation for spinal cord injured patients

In this clinical study, we report the results of functional electrical stimulation for the ambulation of paraplegic patients without long leg braces (LLB), according to the Parastep approach. Of 13 SCI patients with complete neurological lesions included in this trial, 12 progressed to independent ambulation with the aid of the Parastep. The average walking distance was 76 m, with a maximum of 350 m, and the mean speed 0.2 m s-1. Compared to the situation with long leg braces, which in fact are given up by most paraplegic patients, long term home use seems to be much more important. Tolerance of this method is satisfactory. The psychological benefits of the device are remarkable. From this experience, it is concluded that this method is valuable for the restoration of standing and walking in the long term management of spinal cord injury patients.     

Differential diagnosis in patients with disorders of the patellofemoral joint

Anterior knee complaints are difficult diagnostic problems. It cannot be overstated that the most important information available is to be found in the patient's history. Onset, quality, and quantity of symptoms must be assessed. This information is then synthesized to determine the specific functional disabilities resulting from the patient's anterior knee disorder. Once a history is obtained, a consistent, methodical physical examination can be performed to narrow the differential diagnosis. Radiographic evaluation is used to further hone the differential or to confirm the most likely diagnosis. Ultimately, a specific working diagnosis is selected and treatment is tailored to changing the underlying structural or biomechanical abnormalities that led to the patient's complaints.     

18th World Congress, member assembly 1996 and professional board meeting of Rehabilitation International (RI) 9/13-9/20 in Auckland, New Zealand

Anterior knee pain in our military population consititutes a diagnostic and therapeutic problem that is not always easily solved. In recent years, a better understanding of the biomechanics of the patello-femoral joint has contributed to the successful classification and treatment of many patients. However, the cause of pain remains elusive in a significant subset of patients who show no clinical or radiographic evidence of patellar malalignment and continue to have persistent pain despite adequate physiotherapy. In this article, the classification and approach to anterior knee pain are reviewed. Emphasis is placed on dividing patients into four subsets namely; normal tracking, patellar tilt, patellar subluxation and extra-articular causes of anterior knee pain. A more rational approach to the problem can then be employed and successful rehabilitation and/or surgery can be expected.     

Eruption of the permanent upper canine: a radiologic study

Fibroblast-seeded collagen scaffolds or ligament analogs are potentially useful for reconstruction of the anterior cruciate ligament of the knee. To provide lasting benefits, the seeded cells must survive implantation within the harsh synovial environment of the knee joint. Our objective was to determine the in vivo fate of autogenous fibroblast-seeded ligament analogs as a function of fibroblast source (anterior cruciate ligament or skin), implantation site (knee joint or subcutaneous space), and time after implantation (1, 2, 4, 6, or 8 weeks). Before implantation, fibroblasts were labeled with PKH26-GL, a fluorescent membrane dye. Immediately after retrieval of the implant, the viability of the labeled seeded cells was assessed under a fluorescent microscope. Viable seeded fibroblasts remained attached to the collagen fibers within the ligament analogs for at least 4 weeks (skin fibroblasts) or 6 weeks (anterior cruciate ligament fibroblasts) after implantation. A larger number of viable seeded cells were consistently observed in the subcutaneous space than in the knee joint. Scaffold resorption prevented observation at the 8-week time period. Fibroblast-seeded ligament analogs remained viable for prolonged periods in the knee joint and therefore have the potential to influence the formation and remodeling of neoligament tissue after reconstruction of the anterior cruciate ligament.     

Role of extra-articular procedure

This article describes the 1993 role of extra-articular procedures in the treatment of anterior cruciate-deficient knees. Twenty years ago, most operative effort was concentrated on elimination of the pivot shift phenomenon. Newer operative reconstructions made most of the advantages attributed to extraarticular procedures (shorter operating room time, less soft tissue injury, shorter postoperative rehabilitation) no longer true.     

Low dose oral anticoagulation therapy in Chinese children with congenital heart disease

BACKGROUND: Most patients with osteoarthritis (OA) are treated by primary care physicians (in this article, primary care physicians are family physicians and general internists). OBJECTIVE: To describe and compare the self-reported practice patterns of family physicians and general internists for the evaluation and management of severe OA of the knee, including factors that might influence referral for total knee replacement. DESIGN, SETTING, AND PARTICIPANTS: A survey was developed and mailed to randomly selected community family physicians and general internists practicing in Indiana. MAIN OUTCOME MEASURE: Self-reported physician practice patterns regarding OA of the knee. RESULTS: Physical examination was the most common method of evaluating OA of the knee. Family physicians were more likely to examine for crepitation, joint stability, and quadriceps muscle strength than were general internists (P<.05). Patients with OA of the knee treated by family physicians were more likely to receive nonsteroidal anti-inflammatory drugs or oral corticosteroids and were less likely to receive aspirin, acetaminophen, or narcotics compared with patients treated by general internists. Six patient characteristics were rated as positive factors favoring a referral for possible total knee replacement, 8 characteristics were rated as negative, and 5 were rated as not a factor in the decision about referral. CONCLUSIONS: Results from this study suggest that additional research is needed to determine the evaluative techniques for OA of the knee that provide the most useful information for management decisions, the management techniques that maximize patient outcomes, and the criteria that should be used to select patients who would benefit most from referral for possible total knee replacement.     

Non-alcoholic duct destructive chronic pancreatitis

Contact between an anterior cruciate ligament graft and the intercondylar roof has been termed roof impingement. Grafts with impingement sustain permanent damage, and if the injury is extensive enough, then the graft may fail, causing recurrent instability. This study evaluated two mechanical factors that could be responsible for the graft injury associated with roof impingement: an increase in graft tension or elevated pressures between the graft and the roof, or both. An anterior cruciate ligament reconstruction was performed using an Achilles tendon graft in five fresh-frozen cadaveric knees. Using a six-degree-of-freedom load application system, the anterior displacement of the knee with the native anterior cruciate ligament was restored in the reconstructed knee at a flexion angle of 30 degrees and with an anterior force of 200 N applied. Pressure between the graft and intercondylar roof, graft tension, and flexion angle were measured during passive knee extension for three tibial tunnel placements (anterior, center, and posterior). Intercondylar roof impingement increased the contact pressure between the graft and the roof but had no significant effect on graft tension. Therefore, during passive knee extension, the contact pressure between the anterior cruciate ligament graft and the intercondylar roof is a more likely cause of graft damage than increased graft tension.