Effect of accelerated postoperative rehabilitation after tibial tubercle distalisation: A randomised controlled trial protocol.

Patella alta is a clinical condition where the patella is positioned too proximal in relation to the femoral trochlea. Such an abnormality may cause patellar instability and predispose to recurrent patellofemoral dislocations and patellofemoral pain. There are no conclusive guidelines for determining a threshold for too high positioned patella, as several different methods have been described to measure patellar height. As a surgical solution, distalising tibial tubercle osteotomy has been described to correct excessive patellar height. In the early phase of the distalising tibial tubercle osteotomy postoperative protocol, weightbearing and knee flexion are limited with a brace commonly for 4-8 weeks to avoid potential implant failure leading to displacement of the osteotomy or non-union. The potential risks for adverse effects associated with the limitation rehabilitation protocol include a delay in regaining knee range of motion, stiffness and muscle weakness. As a result, recovery from surgery is delayed and may lead to additional procedures and long-term morbidity in knee function. This is a prospective, randomised, controlled, single-blinded, single centre trial comparing a novel accelerated rehabilitation protocol with the traditional, motion restricting rehabilitation protocol. All skeletally mature patients aged 35 years and younger, referred to as the distalising tibial tubercle osteotomy procedure group, are eligible for inclusion in the study. Patients will be randomised to either the fast rehabilitation group or the traditional rehabilitation group. Patients with patellar instability will be additionally treated with medial patellofemoral ligament reconstruction. The hypothesis of the trial is that the novel accelerated rehabilitation protocol will lead to faster recovery and improved functional outcome at 6, 12 and 24 weeks compared with the conservative rehabilitation protocol. A secondary hypothesis is that the complication rate will be similar in both groups. The study will document short-term recovery and the planned follow-up will be 3 years. After the 1-year follow-up, the trial results will be disseminated in a major peer-reviewed orthopaedic publication. Protocol version 3.6, date 28/11/2023.

A Randomized Controlled Trial Comparing a Patella-Stabilizing, Motion-Restricting Knee Brace Versus a Neoprene Nonhinged Knee Brace After a First-Time Traumatic Patellar Dislocation.

BACKGROUND: A traumatic lateral patellar dislocation is a common injury in adolescents and young adults. The majority of first-time dislocations can be treated nonoperatively. Various types of knee braces are used for nonoperative treatment, but evidence on the most preferable bracing method is lacking. PURPOSE: To evaluate the efficacy of a patella-stabilizing, motion-restricting knee brace versus a neoprene nonhinged knee brace for the treatment of a first-time traumatic patellar dislocation at 3 years of follow-up. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A total of 101 skeletally mature patients with a first-time traumatic patellar dislocation were enrolled in the study. After exclusion criteria were applied, 79 patients with a first-time traumatic patellar dislocation were randomized and allocated into 2 study groups: group A, with a patella-stabilizing, motion-restricting knee brace (hinged to allow knee range of motion [ROM] of 0°-30°) and group B, with a neoprene nonhinged knee brace (not restricting any knee motion). Both groups received similar physical therapy instructions and were advised to use the brace continuously for 4 weeks. Overall, 64 patients completed the trial. RESULTS: The redislocation rate in group A was 34.4% (11/32) and in group B it was 37.5% (12/32) (risk difference, -3.1% [95% CI, -26.6% to 20.3%]; P = .794). Patients in group A had less knee ROM than those in group B at 4 weeks (90° vs 115°, respectively; P < .001) and 3 months (125° vs 133°, respectively; P = .028). Patients in group A had more quadriceps muscle atrophy than patients in group B at 4 weeks (24/32 vs 16/32, respectively; P = .048) and 3 months. At 6 months, patients in group B reported better functional outcomes than patients in group A (Kujala score mean difference, 4.6; P = .012), although no clinically relevant difference was found at 3 years. CONCLUSION: The use of a patella-stabilizing, motion-restricting knee brace for 4 weeks after a first-time traumatic patellar dislocation did not result in a statistically significant reduction in redislocations versus a neoprene nonhinged knee brace, although this trial was underpowered to detect more modest differences. Knee immobilization was associated with quadriceps muscle atrophy, less knee ROM, and worse functional outcomes in the first 6 months after the injury. REGISTRATION: NCT01344915 (ClinicalTrials.gov identifier).

The incidence of paediatric ACL injury is increasing in Finland.

PURPOSE: Anterior cruciate ligament (ACL) injury is a common knee injury in paediatric and adolescent patients. The population-based incidence of paediatric ACL injury is, however, unknown. Recent studies suggest increased ACL injury rates among adolescents, especially in active, sports-participating population. The purpose of this study was to investigate the population-based incidence rates of ACL injuries and trends in paediatric ACL reconstruction surgery. METHOD: All ACL injuries were identified (ICD-10 diagnosis code S83.5) leading to hospitalisation or surgery using validated Finnish National Hospital Discharge Register (NHDR) data from 1997 to 2014. The sample comprised 19,961,205 Finnish residents aged less than 18 years at the time of injury. Hospital admissions with the diagnosis code S83.5 were analysed more thoroughly including, sex, age and the need for surgical interventions. RESULTS: During the 18-year study period, 4725 subjects of the study population had sustained an ACL injury. The total ACL injury incidence in study population was 23.3 per 100,000 person-years. The median age of the patients at the time of injury was 16 years (range 4-17). The incidence of ACL injury increased with age, and the highest incidence was observed among 17-year old (113.5 per 100,000 person-years). Incidence rate did not differ between genders. From the total ACL injury population of 4725 hospitalisations, 3168 (67.0%) underwent ACL reconstruction, of which 2988 (94.3%) were treated with arthroscopic reconstruction and 180 (5.6%) with open surgery. In addition, 1557 (33.0%) were treated non-operatively without ACL reconstruction. The annual incidence of ACL injuries in the Finnish paediatric population has increased during the past 15 years. The lowest incidence rate was seen in 1999 (incidence of 17.7 per 100,000 person-years, 195 ACL injuries) and the highest in 2011 (incidence of 31.5 per 100,000 person-years, 346 ACL injuries). The highest increase in ACL injuries was seen in girls aged 13-15 years, with an increase of 143%. CONCLUSION: ACL injury is not a negligible knee injury in the paediatric population. The incidence of paediatric ACL injury has increased during the past 15 years. Moreover, a twofold increase in incidence of paediatric ACL injury was noted during the last 10 years of the study period. Incidence rates among male and female paediatric patients were comparable. LEVEL OF EVIDENCE: III.

Traumatic Patellar Dislocation and Cartilage Injury: A Follow-up Study of Long-Term Cartilage Deterioration.

BACKGROUND: Patellofemoral cartilage deterioration and osteoarthritis are reported to be associated with recurrent patellar dislocation. However, the association between first-time traumatic patellar dislocation and cartilage deterioration is unknown. PURPOSE: The aim of this study was to assess long-term cartilage deterioration in the patellofemoral and tibiofemoral joint after conservatively treated traumatic lateral patellar dislocation. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty patients (mean age, 25 years) who sustained first-time traumatic lateral patellar dislocation with no previous patellofemoral instability symptoms were initially scanned with 1.5-T magnetic resonance imaging (MRI). A follow-up 3-T MRI was conducted, on average, 8 years after first-time lateral patellar dislocation. Subjective instability symptoms and Knee injury and Osteoarthritis Outcome Score were also assessed. RESULTS: In the primary MRI, patellofemoral cartilage injury was seen in 14 of 20 patients (70%). Most (14/15) of the injuries were seen in the patellar cartilage, especially at the medial facet. On the follow-up MRI, patellofemoral cartilage deterioration was visible for all patients. The central patella ( P = .005) seemed especially prone to cartilage deterioration during the follow-up. Half of the patients (10/20) had grade 3-4 cartilage lesions in the patellofemoral joint in the follow-up MRI. In the primary MRI, only 1 patient exhibited tibiofemoral joint cartilage lesions, whereas at the time of follow-up, 10 of 20 patients exhibited tibiofemoral cartilage lesions. The majority of these lesions were considered clinically nonsignificant (International Cartilage Repair Society = 1) and were seen in the lateral compartment (6/10, 60%). Of the 14 patients (36%) with injury to the patellar cartilage, 5 reported subsequent instability of the patellofemoral joint, but this was not associated with more significant cartilage deterioration in the follow-up MRI compared with patients without redislocation. CONCLUSION: While recurrent lateral patellar dislocation is known to lead to degenerative process, a single first-time or infrequently recurring traumatic lateral patellar dislocation also seems to be associated with gradual cartilage deterioration. Traumatic lateral patellar dislocation might initiate gradual degeneration of the cartilage in the patellofemoral joint and can lead to the development of generalized knee osteoarthritis. Instability symptoms of the patellofemoral joint, however, were not related to the severity of the deterioration.

Medial patellofemoral ligament avulsion injury at the patella: classification and clinical outcome.

PURPOSE: To define medial patellofemoral ligament (MPFL) injury characteristics at the patellar attachment and clinical outcome in patients with primary traumatic patellar dislocation and MPFL avulsion injury at the patella. METHODS: Magnetic resonance imaging (MRI) was used to assess patients with primary (first-time) patellar dislocation and MPFL injury at the medial margin of the patella. Fifty-six patients with patellar attachment MPFL injury were enrolled in the study. Thirteen patients underwent surgical fixation of the avulsed MPFL and patellar medial margin osteochondral fracture, and the remaining patellar MPFL injures were treated nonoperatively. Forty-four patients were evaluated clinically at median four (range 1-10) years after patellar dislocation. The follow-up included evaluation of recurrent patellar instability, subjective symptoms, and functional limitations. RESULTS: Three types of patellar MPFL injuries were found; type P0 with ligamentous disruption at the patellar attachment, type P1 with bony avulsion fracture from the medial margin of the patella, and type P2 with bony avulsion involving articular cartilage from the medial facet of the patella. Of the patellar MPFL avulsion injuries that underwent initial surgical fixation, two patients (2/13) reported an unstable patella at follow-up. Fifty-five per cent (17/31) of patellar MPFL avulsion injuries that were treated nonoperatively had recurrent patellar instability (n.s.). The median Kujala score was 90 for patellar avulsion with surgical fixation and 86 for patellar avulsion without surgical fixation (n.s.). CONCLUSION: Patellar attachment MPFL injury showed three different patterns, classified as types P0, P1, and P2. MRI can be used to assess the injury pattern. Patellar MPFL avulsion injuries do not benefit from acute surgical repair compared with nonsurgical treatment. Type P2 patellar MPFL avulsion includes an osteochondral fracture that may require surgical fixation. LEVEL OF EVIDENCE: Prognostic study, Level III.

Incidence of knee dislocation and concomitant vascular injury requiring surgery: a nationwide study.

BACKGROUND: Acute knee (tibiofemoral joint) dislocation is a serious knee injury, although population-based numbers and incidence rates of knee dislocation with or without concomitant vascular injury are unknown. METHODS: The study covered the whole adult population of 4 million persons (aged ≥ 18 years) in Finland during the 11-year period from January 1, 1998, to December 31, 2011. Data on hospitalization caused by acute knee dislocations and concomitant vascular injuries requiring operative treatment were obtained from the nationwide National Hospital Discharge Registry. RESULTS: During the 14-year study period, a total of 837 patients with knee dislocation diagnosis were hospitalized in Finland. The highest incidence rates in men were in persons aged 18 years to 29 years (incidence, 29 per 1 million person-years in 2011), and the incidence decreased by age, while in women, this incidence was rather similar in all age groups. The most common injury mechanism of knee dislocation was low-energy fall at the same level (46%). The median length of hospital stay was 2 days (range, 1-109 days). In 107 cases (13%), knee dislocation required immediate open (69 cases) or closed (38 cases) reduction in the operating room. Popliteal artery injury requiring acute surgical intervention was found in 13 patients (1.6%), and amputation at the level above the tibiofemoral joint was performed for one patient (0.1%). CONCLUSION: This is the first study describing the population-based incidence of acute knee dislocation. Men aged 18 years to 29 years had the highest incidence rates. Half of the injuries were low-energy trauma. Popliteal artery injury requiring surgical intervention was a rare concomitant injury, but when present, the injury required immediate surgical repair to avoid dramatic consequences. LEVEL OF EVIDENCE: Nationwide epidemiologic study, level I.

Medial patellofemoral ligament: anatomy, injury and treatment in the adolescent knee.

PURPOSE OF REVIEW: Traumatic and nontraumatic patellofemoral instability (PFI) in children and adolescents is a complex problem. It is determined by a large number of mechanical and pathomorphologic conditions, mainly seen in nontraumatic dislocations. RECENT FINDINGS: Although conservative treatment with a short immobilization, followed by early passive motion and isometric quadriceps strengthening, can be considered in real traumatic dislocations without any cartilaginous injury, a surgical intervention should be considered in atraumatic cases. As 90% of PFI are nontraumatic and correlated with skeletal deformities, the redislocation rate is reported to be up to 80% after initial conservative treatment. To optimize the results, the causing disorder for PFI has to be considered imperatively. In addition to bony disorder, further risk factors have to be taken into consideration for determining the optimal time for surgery. As biomechanical and clinical studies have shown the importance of the medial patellofemoral complex, especially the medial patellofemoral ligament (MPFL), against patellar lateralization, the reconstruction or minimally invasive double-bundle reconstruction of the MPFL is the main surgical technique to treat PFI in children, as it can be used even in open epiphysial cartilage. Further surgical interventions correcting bone deformities, such as trochleoplasty or tibial tubercle osteotomies addressing lower limb deformities, should be performed after closure of the epiphysial cartilage. SUMMARY: It is the goal of this overview to explain the pathoanatomy of PFI, the demanding clinical and radiological examinations and treatment options.

First-time patellar dislocation: surgery or conservative treatment?

Primary patellar dislocation injures the medial patellofemoral ligament (MPFL), the major soft-tissue stabilizer of the patella, which may lead to recurrent patellar instability. Recurrent patellar dislocation are common and may require surgical intervention. The variation in location of injury of the MPFL and the presence of an osteochondral fracture produces challenges in clinical decision making between nonoperative and operative treatment, including the surgical modality, to repair or reconstruct the MPFL. Current evidence suggests that not all primary dislocations should undergo the same treatment. MPFL reconstruction may theoretically be more reliable than repair, but the optimal time to perform additional bony corrections is not known. A normal or minor dysplastic patellofemoral joint may be suitable for nonoperative treatment, whereas a higher grade of trochlear dysplasia or other significant abnormalities may benefit from surgical treatment. In this paper, we present a treatment algorithm for primary patellar dislocation.

Patellofemoral osteoarthritis in patients with operative treatment for patellar dislocation: a magnetic resonance-based analysis.

PURPOSE: the clinical role of patellofemoral (PF) osteoarthrosis (OA) in the outcome after PF stabilizing surgery is poorly understood. The study hypothesis was that PF cartilage lesions and OA are associated with a poor long-term outcome after PF stabilizing surgery. METHODS: the study cohort included thirty-seven patients who underwent PF stabilizing surgery by traditional nonanatomic procedures and were evaluated a minimum of 10 years (range 10-21) after surgery. PF OA was assessed by magnetic resonance (MR) images and plain radiographs obtained at follow-up. Median patient age at follow-up was 33 years (29-43). RESULTS: at the final follow-up, PF full-thickness cartilage lesions were observed on MR images in 29 (78%) patients. Only 46% of the patients reported satisfaction at follow-up, and dissatisfaction was associated with PF OA (full-thickness articular cartilage loss on MR images; P = 0.022). Especially high incidence, 89%, of medial patellar facet cartilage lesions were found among the patients dissatisfied with the result (16/18 patients) (n.s.). Eight (22%) of the 37 patients reported recurrent patellar instability episodes at follow-up. Median Kujala score was 83 points (range 55-98). CONCLUSION: patellofemoral OA is a significant long-term risk of nonanatomic surgery for patellar instability and has a greater impact on subjective outcome than residual instability more than 10 years after surgery.

Femoral avulsion of the medial patellofemoral ligament after primary traumatic patellar dislocation predicts subsequent instability in men: a mean 7-year nonoperative follow-up study.

BACKGROUND: The clinical relevance of medial patellofemoral ligament (MPFL) injury location in primary patellar dislocation has not been studied. HYPOTHESIS: Prognosis after primary traumatic patellar dislocation may vary by MPFL injury location. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The initial magnetic resonance imaging (MRI) findings in 53 patients with identical nonoperative management were retrospectively analyzed for medial restraint injuries. The MPFL injury sites were classified as follows: femoral, midsubstance, and patellar. Magnetic resonance imaging was used to assess initial and control articular cartilage lesions in the patellofemoral joint. After a mean follow-up of 7 years, 42 patients were evaluated for redislocations, subjective symptoms, and functional limitations. RESULTS: Based on the initial MRIs, MPFL rupture was classified as femoral in 35 patients, midsubstance in 11, and patellar in 7. At follow-up, 15 patients reported an unstable patella (13 femoral, 1 patellar, 1 midsubstance; P = .01) and 9 reported patellar redislocations (8 femoral, 1 midsubstance; P = .05). The proportion of patients who regained their preinjury activity level was significantly smaller among those with femoral MPFL injury than among those with midsubstance or patellar MPFL injury (P = .05). The median Kujala score was as follows: 90 for femoral, 91 for patellar, and 96 for midsubstance (P = .76). Control MRI showed full-thickness patellofemoral cartilage lesions in 50% of the patients, unrelated to MPFL injury location. CONCLUSION: An MPFL avulsion at the femoral attachment in primary traumatic patellar dislocations predicts subsequent patellar instability. The authors suggest that MPFL injury location be taken into account when planning treatment of primary traumatic patellar dislocation.

Treatment with and without initial stabilizing surgery for primary traumatic patellar dislocation. A prospective randomized study.

BACKGROUND: There is no consensus about the management of acute primary traumatic patellar dislocation in young physically active adults. The objective of this study was to compare the clinical outcomes after treatment with and without initial stabilizing surgery for primary traumatic patellar dislocation in young adults. METHODS: Forty young adults, thirty-seven men and three women with a median age of twenty years (range, nineteen to twenty-two years), who had an acute primary traumatic patellar dislocation were randomly allocated to be treated with initial surgical stabilization (eighteen patients, with each receiving one of two types of initial stabilizing procedures) or to be managed with an orthosis (twenty-two patients, including four who had osteochondral fragments removed arthroscopically). After a median of seven years, thirty-eight patients returned for a follow-up examination. Redislocations, subjective symptoms, and functional limitations were evaluated. Radiographs and magnetic resonance images were obtained at the time of randomization, and twenty-nine (76%) patients underwent magnetic resonance imaging at the time of final follow-up. RESULTS: A hemarthrosis as well as injuries of the medial retinaculum and the medial patellofemoral ligament were found on magnetic resonance imaging in all patients at the time of randomization. During the follow-up period, six of the twenty-one nonoperatively treated patients and none of the seventeen patients treated with surgical stabilization had a redislocation (p = 0.02). Four nonoperatively treated patients and two patients treated with surgical stabilization reported painful patellar subluxation. The median Kujala scores were 91 points for the surgically treated patients and 90 points for the nonoperatively treated patients. Thirteen patients in the surgically treated group and fifteen in the nonoperatively treated group regained their former physical activity level. At the time of follow-up, a full-thickness patellofemoral articular cartilage lesion was detected on magnetic resonance imaging in eleven patients; the lesions were considered to be unrelated to the form of treatment. CONCLUSIONS: In a study of young, mostly male adults with primary traumatic patellar dislocation, the rate of redislocation for those treated with surgical stabilization was significantly lower than the rate for those treated without surgical stabilization. However, no clear subjective benefits of initial stabilizing surgery were seen at the time of long-term follow-up.

A mini-invasive adductor magnus tendon transfer technique for medial patellofemoral ligament reconstruction: a technical note.

Patellar dislocations are associated with injuries to the medial patellofemoral ligament (MPFL). Several techniques for MPFL reconstruction have been recently published with some disadvantages involved, including large skin incisions and donor site morbidity. Arthroscopic stabilizing techniques carry the potential of inadequate restoration of MPFL function. We present a minimally invasive technique for MPFL reconstruction using adductor magnus tendon autograft. This technique is easily performed, safe, and provides a stabilizing effect equal to current MPFL reconstructions. Skin incision of only 3-4 cm is located at the level of the proximal half of the patella. After identifying the distal insertion of the adductor magnus tendon, a tendon harvester is introduced to harvest the medial two-thirds of the tendon, while the distal insertion is left intact. The adductor magnus tendon is cut at 12-14 cm from its distal insertion and transferred into the patellar medial margin. Two suture anchors are inserted through the same incision at the superomedial aspect of the patella in the anatomic MPFL origin. The graft is tightened at 30 degrees knee flexion. Aftercare includes 4 weeks of brace treatment with restricted range of motion.

Arthroscopic surgery for primary traumatic patellar dislocation: a prospective, nonrandomized study comparing patients treated with and without acute arthroscopic stabilization with a median 7-year follow-up.

BACKGROUND: No data exist whether patients with primary traumatic patellar dislocation benefit from initial arthroscopic medial repair surgery. PURPOSE: To compare long-term outcomes of patients treated with acute arthroscopic stabilization for patellar dislocation with those treated nonoperatively except for removal of loose bodies. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: The study group included 76 consecutive military recruits (72 men, 4 women), with a median age of 20 years (range, 19-22) at the time of dislocation. Thirty patients (group 1) underwent initial arthroscopic medial retinacular repair, and 46 patients (group 2) were treated without stabilizing surgery, including 11 who had osteochondral fragments arthroscopically removed. Patients with previous patellar dislocations or instability were excluded. Aftercare was identical in both groups. Redislocations, subjective symptoms, and functional limitations were evaluated after a median 7-year follow-up. RESULTS: Sixty-one (80%) patients participated in a follow-up examination. At final follow-up, 8 (23%) redislocations occurred in group 2 and 5 (19%) in group 1 (P = .84). Eight (23%) patients in group 2 and 3 (12%) in group 1 reported patellar subluxations (P = .18). In group 1, 81% regained their preinjury activity level compared with 56% in group 2 (P = .05). Functional outcomes were good in both groups (Kujala scores: 87 for group 1 and 90 for group 2) (P = .22). Regarding the presence of osteoarthritic characteristics in the patellofemoral joint, no statistically significant differences were found between the groups. CONCLUSIONS: Initial arthroscopic medial retinacular repair was not followed by improved patellar stability nor reduced incidence of redislocations compared with nonoperative (except for removal of loose bodies) treatment. Acute arthroscopic medial retinacular repair allowed patients to better regain preinjury activity level than in patients not undergoing retinacular repair. The decision to stabilize the patella by initial arthroscopic surgery should be made with caution.