KOOS pain as a marker for significant knee pain two and six years after primary ACL reconstruction: a Multicenter Orthopaedic Outcomes Network (MOON) prospective longitudinal cohort study.

OBJECTIVE: The prevalence of radiographic osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR) approaches 50%, yet the prevalence of significant knee pain is unknown. We applied three different models of Knee injury and Osteoarthritis Outcome Score (KOOS) thresholds for significant knee pain to an ACLR cohort to identify prevalence and risk factors. DESIGN: Multicenter Orthopaedic Outcomes Network (MOON) prospective cohort patients with a unilateral primary ACLR and normal contralateral knee were assessed at 2 and 6 years. Independent variables included patient demographics, validated Patient Reported Outcomes (PRO; Marx activity score, KOOS), and surgical characteristics. Models included: (1) KOOS criteria for a painful knee = quality of life subscale <87.5 and ≥2 of: KOOSpain <86.1, KOOSsymptoms <85.7, KOOSADL <86.8, or KOOSsports/rec <85.0; (2) KOOSpain subscale score ≤72 (≥2 standard deviations below population mean); (3) 10-point KOOSpain drop from 2 to 6 years. Proportional odds models (alpha ≤ 0.05) were used. RESULTS: 1761 patients of median age 23 years, median body mass index (BMI) 24.8 kg/m(2) and 56% male met inclusion, with 87% (1530/1761) and 86% (1506/1761) follow-up at 2 and 6 years, respectively. At 6 years, n = 592 (39%), n = 131 (9%) and n = 169 (12%) met criteria for models #1 through #3, respectively. The most consistent and strongest independent risk factor at both time-points was subsequent ipsilateral knee surgery. Low 2-year Marx activity score increased the odds of a painful knee at 6 years. CONCLUSIONS: Significant knee pain is prevalent after ACLR; with those who undergo subsequent ipsilateral surgery at greatest risk. The relationship between pain and structural OA warrants further study.

Meniscus treatment and age associated with narrower radiographic joint space width 2-3 years after ACL reconstruction: data from the MOON onsite cohort.

OBJECTIVE: To identify risk factors for radiographic signs of post-traumatic osteoarthritis (OA) 2-3 years after anterior cruciate ligament (ACL) reconstruction through multivariable analysis of minimum joint space width (mJSW) differences in a specially designed nested cohort. METHODS: A nested cohort within the Multicenter Orthopaedic Outcomes Network (MOON) cohort included 262 patients (148 females, average age 20) injured in sport who underwent ACL reconstruction in a previously uninjured knee, were 35 or younger, and did not have ACL revision or contralateral knee surgery. mJSW on semi-flexed radiographs was measured in the medial compartment using a validated computerized method. A multivariable generalized linear model was constructed to assess mJSW difference between the ACL reconstructed and contralateral control knees while adjusting for potential confounding factors. RESULTS: Unexpectedly, we found the mean mJSW was 0.35 mm wider in ACL reconstructed than in control knees (5.06 mm (95% CI 4.96-5.15 mm) vs 4.71 mm (95% CI 4.62-4.80 mm), P < 0.001). However, ACL reconstructed knees with meniscectomy had narrower mJSW compared to contralateral normal knees by 0.64 mm (95% C.I. 0.38-0.90 mm) (P < 0.001). Age (P < 0.001) and meniscus repair (P = 0.001) were also significantly associated with mJSW difference. CONCLUSION: Semi-flexed radiographs can detect differences in mJSW between ACL reconstructed and contralateral normal knees 2-3 years following ACL reconstruction, and the unexpected wider mJSW in ACL reconstructed knees may represent the earliest manifestation of post-traumatic osteoarthritis and warrants further study.

Augmentation of anterior cruciate ligament reconstruction in dogs with prostheses of different stiffnesses.

The purpose of this study was to investigate the biological and biomechanical properties of anterior cruciate ligament (ACL) reconstruction augmented with Dacron prostheses of three different stiffnesses. The ACLs of 36 adult mongrel dogs were removed and the ligament was reconstructed. In 18 dogs, one knee was reconstructed with patellar tendon alone, and the contralateral knee with Dacron augmented patellar tendon. In the remaining 18 dogs, reconstruction was with Dacron augmented patellar tendon with Dacron alone being used for the contralateral control knee. Death was 3 months after surgery, and the reconstructions were examined biologically and biomechanically. The mechanical data were compared with immediate postoperative data obtained from 45 reconstructed fresh cadaveric knees. Tensile testing demonstrated that an increase in failure load was found when the implanted patellar tendon graft was compared with the cadaveric reconstruction. The strength of the Dacron augmented reconstruction showed little change while the Dacron alone graft decreased in strength during the period of implantation. No clear difference was found between the performance of augmentation devices of different stiffnesses. Microangiography showed that grafts were totally revascularized in patellar tendon alone, but not well revascularized in Dacron augmented patellar tendon and Dacron alone reconstruction. The presence of the Dacron appeared to have an adverse effect on revascularization.

Distribution of cellular repopulation and collagen synthesis in a canine anterior cruciate ligament autograft.

Whether the central core of an anterior cruciate ligament autograft reconstruction is nutritionally compromised at a time when revascularization is known to be complete has not been determined by methods that detect matrix synthesis. In a canine model of anterior cruciate ligament reconstruction with patellar tendon autograft, the adequacy of the supply of metabolites for cellular matrix synthesis was determined by autoradiographic analysis. Total collagen synthesis and cellularity were also quantified. Total collagen synthesis was found to be significantly elevated (p = 0.014 by analysis of variance) in the ligament reconstructions as compared with normal anterior cruciate ligaments or patellar tendons but cellularity was not (p = 0.13 by analysis of variance). Autoradiography demonstrated even distribution of [3H]proline incorporation throughout the graft and normal tissue. When revascularization was complete there was an adequate supply of metabolites for cellular synthesis of protein macromolecules within all regions of the ligament reconstruction. At 3 months after reconstruction, the grafts were found to be actively remodeling their collagen matrix. Since the long-term function of an anterior cruciate ligament autograft is dependent on viable fibroblasts to maintain the collagen matrix the canine anterior cruciate ligament reconstruction contains living cells that are able to remodel the matrix under appropriate conditions.

Characterization of hamstring reflexes during anterior cruciate ligament disruption: in vivo results from a goat model.

The existence of an anterior cruciate ligament-hamstring reflex arc, the extent to which these reflexes can protect the knee, and the extent to which they are affected by rupture of the anterior cruciate ligament remain controversial. We evaluated the temporal components of the anterior cruciate ligament-hamstring synergy by simulating an injury to the ligament in a goat model. Reflexive hamstring activation in anesthetized goats was evaluated when the anterior cruciate ligament was loaded with static subfailure, dynamic subfailure, and dynamic failure loads. Reflexive hamstring activation was not found in response to static subfailure loading but was observed in response to dynamic subfailure and failure loading. The latency of the reflex evoked by dynamic failure loading was shorter than that evoked by dynamic subfailure loading. The findings suggest that the extent to which the hamstring reflexes can protect the knee may be bounded by the ability of these muscles to generate force rapidly and the amplitude and time-course of the loads applied to the knee joint. The present data present a framework for further investigation of the contribution of anterior cruciate ligament-hamstring reflexes to the stability of the knee joint under high loads and loading rates.

Anterior cruciate reconstruction using the Jones-Ellison procedure.

We performed a follow-up study of forty consecutive combined Jones-Ellison anterior-cruciate reconstructions in a young, athletic population. The mean interval from injury to operation was 2.7 years. Preoperatively, all patients had a 3+ or 4+ pivot shift and instability. All but five patients had a meniscal tear, and thirty patients had arthritic changes in the knee at the time of operation. Postoperatively only four of the patients had any complaints of giving-way. Although thirty of the patients returned to their previous sports activities, only eight achieved the preinjury level of performance. Arthritic symptoms were present at operation in thirty patients, while thirty-four had no postoperative objective signs of pivot shift or instability.

The syndrome of inappropriate antidiuretic-hormone secretion following spinal fusion.

Ten adolescent and preadolescent patients who underwent posterior spinal fusion for idiopathic scoliosis or spondylolisthesis were examined for the presence or absence of the postoperative syndrome of inappropriate antidiuretic-hormone secretion. For each patient, levels of serum sodium, serum osmolality, urine sodium, urine osmolality, and serum antidiuretic hormone were obtained preoperatively and postoperatively. The investigation clearly showed that the syndrome occurred in each patient, with the level of serum antidiuretic hormone being highest within a few hours postoperatively. This resulted in a reduction of urinary output, the reduction being maximum on the day of operation and the output gradually rising to normal over the next three days. This syndrome and its associated low postoperative urinary output is common after spinal fusion and should be treated with restriction of fluids rather than administration of increased amounts of fluid.

A biomechanical comparison of different surgical techniques of graft fixation in anterior cruciate ligament reconstruction.

Different surgical methods of graft fixation in ACL reconstruction were examined to determine the effects on mechanical properties of the reconstructed ACL. Ten human cadavers were used in this study. Six different types of grafts were studied. The tendon grafts were removed from each cadaver and fixed to femurs and tibias as ACL substitutes with different surgical fixation methods, leaving femur-reconstructed graft-tibia preparations. The surgical techniques used were staple fixation, tying sutures over buttons, and screw fixation. In the latter, the screws were introduced through femoral and tibial drill holes from the outside in order to achieve interference fit as described by Lambert. Tensile testing demonstrated that the original ACL is significantly stronger than the graft used for reconstruction in linear load, stiffness, and maximum tensile strength. All of the failures of the reconstructed ACL grafts occurred at the fixation site, indicating that the mechanically weak link of the reconstructed graft is located at the fixation site. Among the different methods of fixation, one-third of the patellar tendon secured with a cancellous screw, especially with a custom designed large diameter screw, showed significantly higher values. Although many other factors affect the success of ACL reconstruction, our study indicates that the method of surgical fixation is the major factor influencing the graft's mechanical properties in the immediate postoperative period.

Graft tension in anterior cruciate ligament reconstruction. An in vivo study in dogs.

The purpose of this study was to examine the effect of initial tensioning on the outcome of reconstruction of the ACL. The ACLs of 15 adult mongrel dogs were excised and reconstructed. In the first five dogs, the ACLs of both knees were reconstructed using the medial one-third of the patellar tendon. The graft was fixed under a tension of 1 N (0.22 pounds) in one knee and 39 N (8.8 pounds) in the opposite knee. In the remainder of the dogs, the reconstructions were augmented with Dacron prostheses. Tensioning of both graft components in the augmented reconstructions was either with 1 N in one knee and 39 N in the contralateral knee or disproportionate tensions of 1 N and 39 N applied to the autogenous material and to the prosthesis. Sacrifice was 3 months postsurgery and results were examined with microangiography/history and mechanical testing. In the reconstructions with the patellar tendon alone, the biologic study showed poor vascularity and focal myxoid degeneration within the graft pretensioned with a load of 39 N. In the augmented reconstructions, the knees in which both graft materials were fixed with 1 N tension showed the strongest and stiffest reconstruction at 3 months. The study suggests that minimal tension should be applied to the graft materials during surgical reconstruction of the ACL.

Soft playing splint for protection of significant hand and wrist injuries in sports.

A simple custom-made soft splint has been devised to allow safe sports participation for significant hand and wrist injuries. Made from readily available materials, this "rubber splint" has been used successfully in 113 injuries reviewed in this report. This splint is a result of a modification of an original "Duke" splint described by Dobson, Davis, Lincoln, and Basset, (Exhibit at American Academy of Orthopaedic Surgeons, San Francisco, California, 1971) and the soft cast used at the University of Virginia by McCue and Gieck (personal communication).

Articular cartilage contact pressure after tibial tuberosity transfer. A cadaveric study.

Medial transfer of the tibial tuberosity has been commonly used for treatment of recurrent dislocation of the patella and patellofemoral malalignment. In this study, six fresh human cadaveric knees were used. Static intrajoint loads were recorded using Fuji Prescale pressure-sensitive film for contact pressure and contact area determination in a closed kinetic chain knee testing protocol. Peak pressures, average contact pressures, and contact areas of the patellofemoral and tibiofemoral joints were calculated on native intact knee specimens and after tibial tuberosity transfer. All native intact knee specimens had a normal Q angle. Medialization of the tibial tuberosity significantly increased the patellofemoral contact pressure. Medial displacement of the tibial tuberosity also significantly increased the average contact pressure of the medial tibiofemoral compartment and changed the balance of tibiofemoral joint loading. The results of our study suggest that caution should be used when transferring a patellar tendon in the face of a preexisting normal Q angle as this will result in abnormally high peak pressure within the tibiofemoral joint. Overmedialization of the tibial tuberosity should be avoided in the varus knee, the knee after medial meniscectomy, and the knee with preexisting degenerative arthritis of the medial compartment.

Posterior shoulder instability. Surgical versus conservative results with evaluation of glenoid version.

We conducted a retrospective study on 50 patients with recurrent posterior shoulder instability. Twenty-five patients were treated conservatively with a specific rehabilitation program strengthening the rotator cuff. The other 25 patients, who did not improve with rehabilitation, underwent surgical reconstruction, the majority of these being soft tissue repairs. Recurrence in the surgically treated group averaged 72% while that in the conservatively treated group was 96%. However, 50% of those patients treated surgically and 68% of those treated conservatively felt their symptoms were improved. In view of the high recurrence rate with soft tissue reconstruction, computed tomography scans were obtained to evaluate glenoid version. Those patients with posterior shoulder instability were found to have increased glenoid retroversion when compared to an uninjured population (P less than 0.05). Our conclusions based on this study were that 1) specific therapy in the form of rotator cuff strengthening should be the initial form of treatment in patients with posterior shoulder instability, 2) soft tissue surgery has a high rate of recurrence, 3) the return to sports is variable, 4) there appears to be an increased incidence of glenoid retroversion in this patient population, and 5) the incidence of posttraumatic arthritis is low.

Prospective study of osseous, articular, and meniscal lesions in recent anterior cruciate ligament tears by magnetic resonance imaging and arthroscopy.

Fifty-four patients with anterior cruciate ligament tears that were arthroscopically reconstructed within 3 months of initial injury were prospectively evaluated. Patients with grade 3 medial collateral ligament, lateral collateral ligament, or posterior cruciate ligament tears were excluded. Eighty percent of our patients had a bone bruise present on the magnetic resonance image, with 68% in the lateral femoral condyle. Two of the latter findings--an abnormal articular cartilage signal (P = 0.02) and a thin and impacted subchondral bone (P = 0.03)--had a significant relationship with injury to the overlying articular cartilage. Meniscal tears were found in 56% of the lateral menisci and 37% of the medial menisci. A significant association was present between bone bruising on the lateral femoral condyle and the lateral tibial plateau (P = 0.02). Results of our study support the concept that the common mechanism of injury to the anterior cruciate ligament involves severe anterior subluxation with impaction of the posterior tibia on the anterior femur. Determination of the significance of bone bruising, articular cartilage injury, or meniscal tears will require a long-term followup that includes evaluation for arthritis, stability, and function. These 54 patients represent the first cohort evaluated in this ongoing prospective clinical study.

Autologous blood transfusion and intraoperative cell salvage in a patient with homozygous sickle cell disease.

BACKGROUND: Autologous transfusion can eliminate the need for homologous transfusions. In addition, hypotensive anesthesia and devices that salvage red blood cells for return to the patient can reduce operative blood loss. However, blood from patients with sickle cell disease is difficult to store. SUMMARY: A 16-year-old black girl with homozygous sickle cell disease needed surgery for progressive scoliosis. Her family's religious convictions precluded homologous transfusions. During surgery, 400 mL of autologous blood that had been successfully stored was transfused, as was 800 mL of blood salvaged using a cell-saving device, and 3800 mL of nonblood plasma expanders. Intravenous agents were used to maintain hypotension. However, following a rise in the patient's prothrombin and thromboplastin times, four units of homologous packed red cells were transfused with the permission of the patient's parents. CONCLUSIONS: Patients with sickle cell disease can be given hypotensive anesthesia and autologous transfusions of blood donated before surgery and blood salvaged during surgery using a cell-saving device.

Ligamentous injuries of the knee.

Among the most potentially debilitating injuries to the athlete's knee are those injuries involving the ligaments. The unhappy sequelae of instability and premature osteoarthritis may be avoided by prompt, accurate recognition of the injury, appropriate delivery of treatment, and subsequent maintenance of rehabilitation.

Knee injuries in gymnastics.

A review of injury patterns to the knee joint in gymnastics seen at our sport medicine clinic over a six and one-half year period reveals the patellofemoral pain syndrome to be more than twice as frequent as any other type of injury. Sprains are second in frequency but first in order of problems requiring emergency surgical treatment. The intensity of training correlates with the various overuse syndrome encountered, and the perfection of intricate routines and tricks can lead to significant injury of ligaments and menisci.

Hand and wrist injuries in the preadolescent and adolescent athlete.

In this time when physical prowess has been elevated to such a high level, the prepubescent and adolescent athlete have increased demands for performance placed on their immature musculoskeletal system. Although improved skills may result the athlete is exposed to more injury. Prompt, appropriate treatment of the injury with a controlled return to participation may prevent reinjury and disability. To this end, athletes, parents, coaches, trainers, and team physicians must maintain a close rapport for the benefit of the athlete.

Injuries about the hip and pelvis in the young athlete.

Athletic injuries to the hip and pelvis in pediatric and adolescent athletes, although uncommon, may encompass a wide spectrum of entities. A familiarity with this spectrum and a high index of suspicion in the proper clinical setting will ensure timely diagnosis and help to facilitate implementation of a proper treatment plan thereby assuring safe return to play.

Anterior cruciate ligament injuries in the skeletally immature patient.

Injuries to the anterior cruciate ligament in children and youth pose a complex clinical challenge. The literature does not provide the clinician with a well-defined natural history or pathoanatomy, nor does it show agreement as to the outcomes of various treatment choices. Decision making is made difficult by the patients' skeletal and emotional immaturity and by associated intra-articular fracture, physeal fracture, and combination injuries. In an effort to place the problem of ACL injury in children and youth into some perspective and to present an algorithm for management, this article reviews issues in its diagnosis, classification, anatomy, mechanism of injury, and management.

Osteochondritis dissecans in a young pitcher: why early recognition matters.

Osteochondritis dissecans of the humeral capitellum is an unusual, but not rare, complication of repetitive stress to the skeletally immature elbow. This case report of a Little League player demonstrates how untreated underlying osteochondrosis resulted in permanent disability. Radiographs are essential. The differential diagnosis includes infection, cysts, and Panner's disease. For nondisplaced fragments, rest is indicated until pain resolves and range of motion returns; surgery or arthroscopy may be needed to remove or repair displaced fragments.