summary Hallux rigidus is a common foot condition characterized by pain and loss of motion of the 1st MTP joint in adults due to degenerative arthritis. Diagnosis is made with orthogonal radiographs of the foot that may show joint space narrowing and dorsal osteophytes of the 1st MTP joint. Treatment of early disease consists of a trial of nonoperative management with a Morton's extension orthotic. Operative management is indicated for higher grade disease and varies depending on chronicity of symptoms and severity of osteoarthritis. Epidemiology Incidence 2.5% of patients older than 50 years most common location of osteoarthritis in the foot Demographics females > males (2:1) most commonly noted in the 5th and 6th decade of life Risk factors history of trauma to the 1st MTP joint noted in ~80% of patients with unilateral disease high impact sports Etiology Pathophysiology primary etiology unknown acute trauma and repetitive microtrauma predispose to arthritic changes pathoanatomy osteophyte formation and degeneration of the cartilage occur dorsally in early stages and progress to involve the entire joint anatomic variations of first metatarsal may play a role in arthritic predisposition login to view 4 more bullets Associated conditions orthopedic conditions sesamoid arthritis medical conditions gout rheumatoid arthritis seronegative arthropathies Anatomy Osteology first metatarsal shortest and widest Neurovascular medial branch of the medial dorsal cutaneous nerve overlies 1st MTP joint can become irritated by dorsal osteophytes plantarmedial hallucal nerve also supplies the MTP articulation Biomechanics the first MTPJ carries up to ~120% of an individual's body weight with each step Classification Coughlin and Shurnas Classification Exam findings Radiographic findings Grade 0 Stiffness Dorsiflexion of 40-60 degrees (loss of 10-20%) Normal Grade 1 Mild pain at extremes of motion Dorsiflexion of 30-40 degrees (20-50% lost) Mild dorsal osteophyte, normal joint space Grade 2 Moderate pain at extremes of motion, increasingly more constant Dorsiflexion of 10-30 degrees (50-75% lost) Moderate dorsal osteophyte,<50% joint space narrowing Grade 3 Significant stiffness, near constant pain, pain at extreme ROM, no pain at mid-range Dorsiflexion of 10 degrees or less (75-100% lost) Severe dorsal osteophyte, >50% joint space narrowing Grade 4 Significant stiffness, pain at extreme ROM, pain at mid-range of motion Dorsiflexion same as Grade 3 Same as grade III Presentation History pain swelling gait abnormalities difficulty with shoe wear Symptoms first ray and 1st MTP joint pain worse with push off or lift-off phase of gait dorsal medial foot paresthesia due to dorsal osteophytes and compression of medial dorsal cutaneous nerve transfer metatarsalgia Physical exam inspection swelling of the 1st MTP joint dorsal prominence over the 1st MTP joint (due to dorsal osteophytes) severe disease may present with hyperextension deformity skin irritation and redness from shoe wear motion limited dorsiflexion pain with terminal dorsiflexion login to view 1 more bullet inverted gait neurovascular decreased push-off strength decreased sensation over distal aspect of medial dorsal foot login to view 1 more bullet provocative tests TTP over the first MTP pain with grind test login to view 1 more bullet Imaging Radiographs recommended views weight-bearing AP, lateral, sesamoid and oblique views of the foot findings dorsal osteophytes joint space narrowing subchondral sclerosis and cysts MRI indications rarely needed suspected osteochondral lesion with normal radiographs can better characterize mild osteoarthritis findings osteochondral lesions Treatment Nonoperative NSAIDS, activity modification, intra-articular injections & Morton's extension orthotic indications login to view 1 more bullet outcomes login to view 2 more bullets Operative dorsal cheilectomy indications login to view 3 more bullets contraindications login to view 4 more bullets outcomes login to view 3 more bullets Osteotomy (e.g. Moberg procedure) indications login to view 2 more bullets technique login to view 1 more bullet outcomes login to view 2 more bullets Resection arthroplasty (Keller procedure) indications login to view 1 more bullet contraindications login to view 2 more bullets outcomes login to view 3 more bullets Prosthetic Arthroplasty indications login to view 1 more bullet contraindications login to view 3 more bullets technique login to view 1 more bullet outcomes login to view 8 more bullets Arthrodesis indications login to view 3 more bullets procedure login to view 6 more bullets outcomes login to view 3 more bullets Techniques NSAIDS, activity modification, intra-articular injections & Morton's extension orthotic activity modifications avoid activities that lead to excessive great toe dorsiflexion intra-articular injections both corticosteroid and sodium hyaluronate injections have been shown to significantly improve pain scores at 4 and 8 week follow-up in low-grade disease types of orthotics Morton's extension with stiff foot plate is the mainstay of treatment login to view 1 more bullet stiff sole shoe and shoe box stretching may also be used Dorsal cheilectomy technique dorsal approach with complete synovectomy remove up to 30% of the dorsal aspect of the metatarsal head along with dorsal osteophyte resection login to view 1 more bullet the goal of surgery is to obtain 70-90% of dorsiflexion intraoperatively Dorsal closing wedge osteotomy of the proximal phalanx (Moberg procedure) technique increases dorsiflexion by decreasing the plantar flexion arc of motion may be performed with cheilectomy to increase dorsiflexion Resection arthroplasty (Keller Procedure) technique involves removing the base of the first proximal phalanx interposition risk of hyperextension (cock-up deformity), weakness with push-off, and transfer metatarsalgia (decreased with capsular interposition) Prosthetic arthroplasty technique hemiarthroplasty login to view 4 more bullets total joint arthroplasty login to view 7 more bullets Arthrodesis technique compression and internal fixation can be achieved with wires, pins, lag screws, dual crossed screws and plates login to view 1 more bullet preferred surgical alignment 5 degrees of valgus in relation to the metatarsal shaft 15 degrees of dorsiflexion in relation to the floor best way to assess this intraoperatively is with foot plate to simulate weight bearing with 4-8mm of clearance of toe from plate structural bone grafting technique login to view 2 more bullets complications fusion in excessive dorsiflexion causes pain at tip of the toe, over the IP joint, and under the 1st metatarsal with excessive dorsiflexion fusion in excessive plantar flexion causes increased pressure at the tip of the toe fusion in excessive valgus increases the risk of IP joint degeneration Complications Progression of arthritis may occur after cheilectomy conversion to arthrodesis needed in 7-9% of patients within 10 years Failed arthroplasty risk factors early generation implants (especially silicone implants) login to view 2 more bullets treatment implant resection, synovectomy if there is isolated great toe pain implant resection, bone grafting, and arthrodesis if there is great toe pain with lesser toe metatarsalgia Malunion incidence 16% after arthrodesis may lead to transfer metatarsalgia arthritis of the hallux interphalangeal joint and difficulty with push off Nonunion incidence 5-10% after arthrodesis login to view 1 more bullet treatment revision arthrodesis with bone grafting First MTP joint cock-up deformity risk factors keller resection arthroplasty treatment first MTP joint arthrodesis Hallux IP joint osteoarthritis incidence 15% of patients following hallux MTP joint arthrodesis risk factors hallux MTP joint arthrodesis treatment usually asymptomatic Symptomatic hardware Instability may occur after excessive resection during a cheilectomy Infection < 2% of cases Prognosis Natural history of disease radiographic progression may not always correlate with symptom progression Return to activity after arthrodesis 96% patient satisfaction rate with respect to post-operative activity level high rate of return to hiking (92%), golf (80%), jogging (75%), tennis (75%)