Robert M Kay, MD

Dr. Kay received his undergraduate degree from Harvard College and his medical degree from The Johns Hopkins University School of Medicine. He completed his residency in orthopaedic surgery at University of California Los Angeles and a fellowship in pediatric orthopaedics at Atlanta Scottish Rite Childrens Medical Center. Dr. Kay has published over 70 peer-reviewed articles and numerous book chapters and is active in several organizations including the American Academy of Orthopaedic Surgeons, Pediatric Orthopaedic Society of North America, American Academy of Cerebral Palsy and Developmental Medicine and the Gait and Clinical Movement Analysis Society. Dr. Kay has been the director of the Motion Analysis Laboratory since 1997.

• Dr. Robert Kay Named Chief of Staff at Childrens Hospital Los Angeles

• Percutaneous tendon lengthening and selective percutaneous myofascial lengthening in children with cerebral palsy: Establishing surgical indications using the Delphi method. J Child Orthop. 2026 Jul 22; 18632521261466699.. View in PubMed
• Assessment and Treatment of Varus Foot Deformity in Children with Cerebral Palsy: A Review. J Clin Med. 2026 Feb 02; 15(3).. View in PubMed
• Unpacking Social Disadvantage Metrics in Neuromuscular Conditions: Area Deprivation Index Versus Child Opportunity Index. J Pediatr Soc North Am. 2025 Nov; 13:100257.. View in PubMed
• Risk Factors for Avascular Necrosis in Children With Cerebral Palsy Following Varus Derotation Osteotomy. J Pediatr Orthop. 2025 Jul 14.. View in PubMed
• A Prospective, Randomized Comparison of Functional Bracing and Spica Casting for Femoral Fractures Showed Equivalent Early Outcomes. J Bone Joint Surg Am. 2025 Jun 26; 107(16):1769-1776.. View in PubMed
• Impact of Age on Gait Deviations and Function After Single Event Multilevel Surgery in Children With Cerebral Palsy. J Pediatr Orthop. 2025 Aug 01; 45(7):416-422.. View in PubMed
• An Analysis of Reoperations Following Proximal Femoral Varus Derotational Osteotomy in Children with Cerebral Palsy. JB JS Open Access. 2025 Jan-Mar; 10(1).. View in PubMed
• Outcomes of Triceps Surae Lengthening Surgery in Children With Charcot-Marie-Tooth Disease: A Multisite Investigation. J Pediatr Orthop. 2025 Apr 01; 45(4):226-233.. View in PubMed
• Timely Hip Surgery Access in Children With Cerebral Palsy: Unaffected by Social Disadvantage at a Large Urban Safety Net Hospital. J Pediatr Orthop. 2025 Feb 01; 45(2):e138-e142.. View in PubMed
• Hip Surgery is Not More Painful Than Spine Surgery in Children With Cerebral Palsy. J Pediatr Orthop. 2024 Oct 01; 44(9):e803-e808.. View in PubMed
• Pediatric Outcomes Data Collection Instrument Scores Within Gross Motor Function Classification Scale Levels and Functional Mobility Scale Ratings in Individuals With Cerebral Palsy. J Pediatr Orthop. 2024 Jul 01; 44(6):e542-e548.. View in PubMed
• Drop Foot With Posterior Tibialis Weakness Treated With Peroneus Longus Transfer in a Child: A Case Report. JBJS Case Connect. 2024 04 01; 14(2).. View in PubMed
• Does Size Really Matter? Incidence of Periprosthetic Fractures After Femoral Osteotomy in Patients With Cerebral Palsy. J Pediatr Orthop. 2024 May-Jun 01; 44(5):e452-e456.. View in PubMed
• Update on the reliability of gait analysis interpretation in cerebral palsy: Inter-institution agreement. Gait Posture. 2024 03; 109:109-114.. View in PubMed
• Anterior Distal Femoral Hemiepiphysiodesis Does Not Change Pelvic Tilt in Children With Cerebral Palsy. J Pediatr Orthop. 2024 Feb 01; 44(2):76-81.. View in PubMed
• Predictors of Changes in Pelvic Rotation after Surgery with or without Femoral Derotational Osteotomy in Ambulatory Children with Cerebral Palsy. Bioengineering (Basel). 2023 Oct 18; 10(10).. View in PubMed
• Anterior distal femoral hemiepiphysiodesis in children with cerebral palsy: Establishing surgical indications and techniques using the modified Delphi method and literature review. J Child Orthop. 2023 Jun; 17(3):292-294.. View in PubMed
• Persistent increase in anterior pelvic tilt after hamstring lengthening in children with cerebral palsy. Gait Posture. 2023 06; 103:184-189.. View in PubMed
• Gait Analysis Characteristics in Relapsed Clubfoot. J Pediatr Orthop. 2023 Feb 01; 43(2):65-69.. View in PubMed
• Distal femoral extension osteotomy and patellar tendon advancement or shortening in ambulatory children with cerebral palsy: A modified Delphi consensus study and literature review. J Child Orthop. 2022 Dec; 16(6):442-453.. View in PubMed
• Assessment of foot alignment and function for ambulatory children with cerebral palsy: Results of a modified Delphi technique consensus study. J Child Orthop. 2022 Apr; 16(2):111-120.. View in PubMed
• Finding consensus for hamstring surgery in ambulatory children with cerebral palsy using the Delphi method. J Child Orthop. 2022 Feb; 16(1):55-64.. View in PubMed
• Anterior distal femoral hemiepiphysiodesis in children with cerebral palsy: Establishing surgical indications and techniques using the modified Delphi method and literature review. J Child Orthop. 2022 Feb; 16(1):65-74.. View in PubMed
• Variation in Functional Mobility Within Gross Motor Function Classification System Levels. J Pediatr Orthop. 2022 Apr 01; 42(4):209-214.. View in PubMed
• Tranexamic acid use decreases transfusion rate in children with cerebral palsy undergoing proximal femoral varus derotational osteotomy. Medicine (Baltimore). 2022 Jan 14; 101(2):e28506.. View in PubMed
• Pre-operative nutrition assessments do not improve outcomes in cerebral palsy patients undergoing varus derotational osteotomy. Medicine (Baltimore). 2021 Nov 24; 100(47):e27776.. View in PubMed
• Calcaneal Sliding Osteotomy Versus Calcaneal Lengthening Osteotomy for Valgus Foot Deformity Correction in Children With Cerebral Palsy. J Pediatr Orthop. 2021 Jul 01; 41(6):e433-e438.. View in PubMed
• Distal rectus femoris surgery in children with cerebral palsy: results of a Delphi consensus project. J Child Orthop. 2021 Jun 01; 15(3):270-278.. View in PubMed
• Quantitative Computed Tomography Assessment of Bone Deficits in Ambulatory Children and Adolescents with Spina Bifida: Importance of Puberty. JBMR Plus. 2020 Dec; 4(12):e10427.. View in PubMed
• Anterior distal femoral hemiepiphysiodesis with and without patellar tendon shortening for fixed knee flexion contractures in children with cerebral palsy. J Child Orthop. 2020 Oct 01; 14(5):415-420.. View in PubMed
• Indications for gastrocsoleus lengthening in ambulatory children with cerebral palsy: a Delphi consensus study. J Child Orthop. 2020 Oct 01; 14(5):405-414.. View in PubMed
• Hip Dysplasia Is Not More Common in W-Sitters. Clin Pediatr (Phila). 2020 10; 59(12):1074-1079.. View in PubMed
• Pre-operative methicillin resistant Staphylococcus aureus results do not predict surgical site infections in children undergoing varus derotational osteotomy. Medicine (Baltimore). 2020 Jun 26; 99(26):e20517.. View in PubMed
• Response to comment on Siddiqui et al: ‘Femoral shaft fractures in children with non-ambulatory neuromuscular disorders can be effectively treated using flexible intramedullary nails’. J Child Orthop. 2020 Jun 01; 14(3):243-244.. View in PubMed
• Split Tibialis Anterior Tendon Transfer to The Peroneus Brevis or Tertius for the Treatment of Varus Foot Deformities in Children with Static Encephalopathy: A retrospective case series. J Am Acad Orthop Surg Glob Res Rev. 2020 05; 4(5):e2000044.. View in PubMed
• Femoral shaft fractures in children with non-ambulatory neuromuscular disorders can be effectively treated using flexible intramedullary nails. J Child Orthop. 2020 Apr 01; 14(2):132-138.. View in PubMed
• Establishing surgical indications for hamstring lengthening and femoral derotational osteotomy in ambulatory children with cerebral palsy. J Child Orthop. 2020 Feb 01; 14(1):50-57.. View in PubMed
• Fever after varus derotational osteotomy is common, but not a risk factor for infection. Medicine (Baltimore). 2020 Jan; 99(1):e18613.. View in PubMed
• Comparison of plate and screw constructs versus screws only for anterior distal femoral hemiepiphysiodesis in children. J Pediatr Orthop B. 2020 Jan; 29(1):53-61.. View in PubMed
• Causes of out-toeing gait in children with cerebral palsy. Gait Posture. 2020 02; 76:141-145.. View in PubMed
• Rectus Femoris Transfer Surgery Worsens Crouch Gait in Children With Cerebral Palsy at GMFCS Levels III and IV. J Pediatr Orthop. 2019 Oct; 39(9):466-471.. View in PubMed
• Effect of Early Weightbearing Following Open Reduction and Internal Fixation of Unstable Ankle Fractures on Wound Complications or Failures of Fixation. Foot Ankle Int. 2019 Dec; 40(12):1397-1402.. View in PubMed
• Percutaneous Hamstring Lengthening Surgery is as Effective as Open Lengthening in Children With Cerebral Palsy. J Pediatr Orthop. 2019 Aug; 39(7):366-371.. View in PubMed
• Synovial fluid cell counts and its role in the diagnosis of paediatric septic arthritis. J Child Orthop. 2019 Aug 01; 13(4):417-422.. View in PubMed
• Outcomes of salvage hip surgery in children with cerebral palsy. J Pediatr Orthop B. 2019 Jul; 28(4):314-319.. View in PubMed
• The Incidence of Pin Tract Infections and Septic Arthritis in Percutaneous Distal Femur Pinning. J Pediatr Orthop. 2019 Jul; 39(6):e462-e466.. View in PubMed
• Impact of tranexamic acid use on blood loss and transfusion rates following femoral varus derotational osteotomy in children with cerebral palsy. J Child Orthop. 2019 Apr 01; 13(2):190-195.. View in PubMed
• Pre-operative hamstring length and velocity do not explain the reduced effectiveness of repeat hamstring lengthening in children with cerebral palsy and crouch gait. Gait Posture. 2019 02; 68:323-328.. View in PubMed
• Foam Padding in Postoperative Lower Extremity Casting: An Inexpensive Way to Protect Patients. J Pediatr Orthop. 2018 Sep; 38(8):e470-e474.. View in PubMed
• Reliability of patellar height indices in children with cerebral palsy and spina bifida. J Child Orthop. 2017 Aug 01; 11(4):249-255.. View in PubMed
• Prevalence of specific gait abnormalities in children with cerebral palsy revisited: influence of age, prior surgery, and Gross Motor Function Classification System level. Dev Med Child Neurol. 2017 01; 59(1):79-88.. View in PubMed
• Accessory Navicular is Associated With Wider and More Prominent Navicular Bone in Pediatric Patients by Radiographic Measurement. J Pediatr Orthop. 2016 Jul-Aug; 36(5):521-5.. View in PubMed
• Variability of the Anterior Humeral Line in Normal Pediatric Elbows. J Pediatr Orthop. 2016 Mar; 36(2):e14-6.. View in PubMed
• Integration of Th17- and Lymphotoxin-Derived Signals Initiates Meningeal-Resident Stromal Cell Remodeling to Propagate Neuroinflammation. Immunity. 2015 Dec 15; 43(6):1160-73.. View in PubMed
• Anterior Percutaneous Hemiepiphysiodesis of the Distal Aspect of the Femur: A New Technique: A Case Report. JBJS Case Connect. 2015 Oct-Dec; 5(4):e95.. View in PubMed
• Knee Pain and Patellofemoral Symptoms in Patients With Cerebral Palsy. J Pediatr Orthop. 2015 Jul-Aug; 35(5):519-22.. View in PubMed
• Long-term ambulatory change after lower extremity orthopaedic surgery in children with cerebral palsy: a retrospective review. J Pediatr Orthop. 2015 Apr-May; 35(3):285-9.. View in PubMed
• Foam padding in casts accommodates soft tissue swelling and provides circumferential strength after fixation of supracondylar humerus fractures. J Pediatr Orthop. 2015 Jan; 35(1):24-7.. View in PubMed
• A line drawn along the radial shaft misses the capitellum in 16% of radiographs of normal elbows. J Pediatr Orthop. 2014 Dec; 34(8):763-7.. View in PubMed
• Silent compartment syndrome in children: a report of five cases. J Pediatr Orthop B. 2014 Sep; 23(5):467-71.. View in PubMed
• Heterotopic Ossification Excision Improves Kinetic and Kinematic Gait Parameters as Demonstrated by Computerized Motion Analysis: A Case Report. JBJS Case Connect. 2013 Nov 13; 3(4 Suppl 3):e109.. View in PubMed
• Heterotopic Ossification Excision Improves Kinetic and Kinematic Gait Parameters as Demonstrated by Computerized Motion Analysis: A Case Report. JBJS Case Connect. 2013 Oct 23; 3(4 Suppl 2):e1051-7.. View in PubMed
• Repeat hamstring lengthening for crouch gait in children with cerebral palsy. J Pediatr Orthop. 2013 Jul-Aug; 33(5):501-4.. View in PubMed
• Impact of gait analysis on correction of excessive hip internal rotation in ambulatory children with cerebral palsy: a randomized controlled trial. Dev Med Child Neurol. 2013 Oct; 55(10):919-25.. View in PubMed
• Transverse plane gait problems in children with cerebral palsy. J Pediatr Orthop. 2013 Jun; 33(4):422-30.. View in PubMed
• Assessment of human exposures to animal vaccines using poison control records, 2000-2009. Zoonoses Public Health. 2014 May; 61(3):175-80.. View in PubMed
• Outcomes of lower extremity orthopedic surgery in ambulatory children with cerebral palsy with and without gait analysis: results of a randomized controlled trial. Gait Posture. 2013 Jun; 38(2):236-41.. View in PubMed
• Differences in implementation of gait analysis recommendations based on affiliation with a gait laboratory. Gait Posture. 2013 Feb; 37(2):206-9.. View in PubMed
• Surgical management of hip subluxation and dislocation in children with cerebral palsy: isolated VDRO or combined surgery? J Pediatr Orthop. 2011 Dec; 31(8):858-63. Huh K, Rethlefsen SA, Wren TA , Kay . View in PubMed
• Perioperative ketorolac use in children undergoing lower extremity osteotomies. J Pediatr Orthop. 2011 Oct-Nov; 31(7):783-6.. View in PubMed
• Orthopedic surgeons are less likely to see children now for fracture care compared with 10 years ago. J Pediatr. 2012 Mar; 160(3):505-7.. View in PubMed
• Cerebral palsy: clinical care and neurological rehabilitation. Lancet Neurol. 2011 Sep; 10(9):844-52.. View in PubMed
• Influence of gait analysis on decision-making for lower extremity orthopaedic surgery: Baseline data from a randomized controlled trial. Gait Posture. 2011 Jul; 34(3):364-9.. View in PubMed
• A new surgical technique for the treatment of supracondylar humerus fracture malunions in children. J Child Orthop. 2011 Aug; 5(4):305-12.. View in PubMed
• Orthopaedic issues in children and adolescents with central nervous system tumors. J Pediatr Rehabil Med. 2011; 4(1):71-8.. View in PubMed
• Bone density and size in ambulatory children with cerebral palsy. Dev Med Child Neurol. 2011 Feb; 53(2):137-41.. View in PubMed
• Complications of ketorolac use in children undergoing operative fracture care. J Pediatr Orthop. 2010 Oct-Nov; 30(7):655-8.. View in PubMed
• Effect of high-frequency, low-magnitude vibration on bone and muscle in children with cerebral palsy. J Pediatr Orthop. 2010 Oct-Nov; 30(7):732-8.. View in PubMed
• Classification systems in cerebral palsy. Orthop Clin North Am. 2010 Oct; 41(4):457-67.. View in PubMed
• Excessive hip flexion during gait in patients with static encephalopathy: an examination of contributing factors. J Pediatr Orthop. 2010 Sep; 30(6):562-7.. View in PubMed
• Achilles tendon length and medial gastrocnemius architecture in children with cerebral palsy and equinus gait. J Pediatr Orthop. 2010 Jul-Aug; 30(5):479-84.. View in PubMed
• Development of calcaneal gait without prior triceps surae lengthening: an examination of predictive factors. J Pediatr Orthop. 2010 Apr-May; 30(3):240-3.. View in PubMed
• Static and dynamic gait parameters before and after multilevel soft tissue surgery in ambulating children with cerebral palsy. J Pediatr Orthop. 2010 Mar; 30(2):174-9.. View in PubMed
• Distal humerus osteotomy for supracondylar fracture malunion in children: a study of perioperative complications. Am J Orthop (Belle Mead NJ). 2010 Jan; 39(1):22-5.. View in PubMed
• Osteoporosis management: a perspective based on bisphosphonate data from randomised clinical trials and observational databases. Int J Clin Pract. 2009 Dec; 63(12):1792-804.. View in PubMed
• The Dega osteotomy: a versatile osteotomy in the treatment of developmental and neuromuscular hip pathology. J Pediatr Orthop. 2009 Oct-Nov; 29(7):676-82.. View in PubMed
• Effects of preoperative gait analysis on costs and amount of surgery. J Pediatr Orthop. 2009 Sep; 29(6):558-63.. View in PubMed
• A new classification system predictive of complications in surgically treated pediatric humeral lateral condyle fractures. J Pediatr Orthop. 2009 Sep; 29(6):602-5.. View in PubMed
• Malignant peripheral nerve sheath tumor of the lumbar spine. Am J Orthop (Belle Mead NJ). 2009 May; 38(5):E89-92.. View in PubMed
• Predictors of outcome of distal rectus femoris transfer surgery in ambulatory children with cerebral palsy. J Pediatr Orthop B. 2009 Mar; 18(2):58-62.. View in PubMed
• The recurrent clubfoot: can gait analysis help us make better preoperative decisions? Clin Orthop Relat Res. 2009 May; 467(5):1214-22. Sankar WN, Rethlefsen SA, Weiss J, Kay RM . . View in PubMed
• Complications with flexible nailing of femur fractures more than double with child obesity and weight >50 kg. J Child Orthop. 2009 Feb; 3(1):53-8.. View in PubMed
• Delaying treatment of supracondylar fractures in children: has the pendulum swung too far? J Bone Joint Surg Br. 2008 Sep; 90(9):1228-33. Ramachandran M, Skaggs DL, Crawford HA, Eastwood DM, Lalonde F . View in PubMed
• Timing of the presentation of urethrocutaneous fistulas after hypospadias repair in pediatric patients. J Urol. 2008 Oct; 180(4 Suppl):1753-6.. View in PubMed
• Incidence of occult fracture in children with acute ankle injuries. J Pediatr Orthop. 2008 Jul-Aug; 28(5):500-1.. View in PubMed
• “Kinematic and kinetic evaluation of the ankle joint before and after tendo Achilles lengthening in patients with spastic diplegia”. J Pediatr Orthop. 2008 Apr-May; 28(3):392.. View in PubMed
• Concurrent and discriminant validity of Spanish language instruments for measuring functional health status. J Pediatr Orthop. 2008 Mar; 28(2):199-212.. View in PubMed
• How safe is the operative treatment of Gartland type 2 supracondylar humerus fractures in children? J Pediatr Orthop. 2008 Mar; 28(2):139-41. Skaggs DL, Sankar WN, Albrektson J, Vaishnav S, Choi PD, K . View in PubMed
• Abduction pillow immobilization following hip surgery: a welcome alternative for selected patients. J Child Orthop. 2007 Nov; 1(5):299-305.. View in PubMed
• Gillette Gait Index as a gait analysis summary measure: comparison with qualitative visual assessments of overall gait. J Pediatr Orthop. 2007 Oct-Nov; 27(7):765-8.. View in PubMed

• Wren, Tishya
• Powers, Christopher