{
  "resourceType": "ActivityDefinition",
  "id": "clamshell",
  "url": "https://bodyiq.dev/fhir/ActivityDefinition/clamshell",
  "version": "1",
  "name": "Clamshell",
  "title": "Clamshell",
  "status": "draft",
  "experimental": true,
  "description": "Sidelying hip external rotation exercise. Patient lies on side with hips and knees bent, feet together, and opens top knee like a clamshell.",
  "useContext": [
    {
      "code": {
        "system": "http://terminology.hl7.org/CodeSystem/usage-context-type",
        "code": "user"
      },
      "valueCodeableConcept": {
        "text": "difficulty: beginner"
      }
    }
  ],
  "topic": [
    {
      "coding": [
        {
          "system": "https://bodyiq.dev/fhir/CodeSystem/exercise",
          "code": "clamshell",
          "display": "Clamshell"
        }
      ]
    }
  ],
  "bodySite": [
    {
      "coding": [
        {
          "system": "https://bodyiq.dev/fhir/CodeSystem/exercise",
          "code": "hip",
          "display": "Hip"
        },
        {
          "system": "http://snomed.info/sct",
          "code": "24136001",
          "display": "Structure of hip joint"
        }
      ],
      "text": "Hip"
    }
  ],
  "kind": "ServiceRequest",
  "dosage": [
    {
      "text": "3×15-20 reps per side, 2-3x/week"
    }
  ],
  "usage": "Evidence: strong. Glute med 26-67% MVIC; highest glute med-to-TFL ratio (115) among exercises [Selkowitz 2013]; 60° hip flexion optimal [Willcox 2013]",
  "note": [
    {
      "text": "Quiet trunk, stacked hips — glute med rotates the femur",
      "authorString": "focus:internal"
    },
    {
      "text": "Open the top knee toward the ceiling",
      "authorString": "focus:external"
    },
    {
      "text": "Keep the feet glued together throughout",
      "authorString": "focus:external"
    },
    {
      "text": "Hand on the top hip stops it from rolling backward",
      "authorString": "focus:tactile"
    }
  ],
  "relatedArtifact": [
    {
      "type": "citation",
      "label": "kisner-therapeutic-2017",
      "citation": "Kisner C, Colby LA, Borstad J. (2017). Therapeutic Exercise: Foundations and Techniques"
    },
    {
      "type": "citation",
      "label": "acsm-guidelines-2021",
      "citation": "American College of Sports Medicine. (2021). ACSM's Guidelines for Exercise Testing and Prescription",
      "document": {
        "url": "https://doi.org/10.4135/9781412994149.n165"
      }
    },
    {
      "type": "citation",
      "label": "va-hip-knee-oa-2020",
      "citation": "Matthew Bair MD MS, John Cody MD, Jess Edison MD, et al.. (2020). The Non-Surgical Management of Hip & Knee Osteoarthritis (OA) (2020)",
      "document": {
        "url": "https://doi.org/10.1016/j.ijotn.2020.100840"
      }
    },
    {
      "type": "citation",
      "label": "cibulka-hip-oa-cpg-2017",
      "citation": "Cibulka MT, Bloom NJ, Enseki KR, et al.. (2017). Hip Pain and Mobility Deficits-Hip Osteoarthritis: Revision 2017",
      "document": {
        "url": "https://doi.org/10.2519/jospt.2017.0301"
      }
    },
    {
      "type": "citation",
      "label": "willcox-clamshell-hip-angle-2013",
      "citation": "Willcox EL, Burden AM. (2013). The Influence of Varying Hip Angle and Pelvis Position on Muscle Recruitment Patterns of the Hip Abductor Muscles During the Clam Exercise",
      "document": {
        "url": "https://doi.org/10.2519/jospt.2013.4004"
      }
    },
    {
      "type": "citation",
      "label": "nam-sidelying-hip-exercises-2025",
      "citation": "Nam SJ, Oh DW. (2025). Comparison of the Effects of 3 Side-Lying Exercises on Electromyographic Activities of Lumbopelvic Muscles in Young Females With Hip Abductor Weakness",
      "document": {
        "url": "https://doi.org/10.1016/j.jmpt.2025.09.016"
      }
    },
    {
      "type": "citation",
      "label": "mcbeth-hip-emg-runners-2012",
      "citation": "McBeth JM, Earl-Boehm JE, Cobb SC, Huddleston WE. (2012). Hip Muscle Activity During 3 Side-Lying Hip-Strengthening Exercises in Distance Runners",
      "document": {
        "url": "https://doi.org/10.4085/1062-6050-47.1.15"
      }
    },
    {
      "type": "citation",
      "label": "selkowitz-gluteal-tfl-2013",
      "citation": "Selkowitz DM, Beneck GJ, Powers CM. (2013). Which Exercises Target the Gluteal Muscles While Minimizing Activation of the Tensor Fascia Lata?",
      "document": {
        "url": "https://doi.org/10.2519/jospt.2013.4116"
      }
    },
    {
      "type": "citation",
      "label": "sidorkewicz-glutmed-tfl-2014",
      "citation": "Sidorkewicz N, Cambridge ED, McGill SM. (2014). Examining the Effects of Altering Hip Orientation on Gluteus Medius and Tensor Fascae Latae Interplay",
      "document": {
        "url": "https://doi.org/10.1016/j.clinbiomech.2014.09.002"
      }
    },
    {
      "type": "citation",
      "label": "kim-deep-gluteal-mri-2025",
      "citation": "Kim S, Burland JP, Morgan KD, et al.. (2025). Superficial and Deep Gluteal Muscle Activation During Common Therapeutic Exercises: A Muscle Functional MRI Analysis",
      "document": {
        "url": "https://doi.org/10.1249/01.mss.0001159448.86162.5e"
      }
    }
  ],
  "extension": [
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Gluteus Medius"
        },
        {
          "url": "role",
          "valueCode": "primary"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "78333006"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Piriformis"
        },
        {
          "url": "role",
          "valueCode": "synergist"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "75699001"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Gluteus Maximus"
        },
        {
          "url": "role",
          "valueCode": "synergist"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "206007"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Tensor Fasciae Latae"
        },
        {
          "url": "role",
          "valueCode": "secondary"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "28190000"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Gluteus Minimus"
        },
        {
          "url": "role",
          "valueCode": "synergist"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "75297007"
          }
        }
      ]
    }
  ]
}